English Language Questions for CLAT | QB Set 56

Topic: Science – Genetics, Evolution and Species Classification
Difficulty Level: Moderate to Difficult
Passage Type: Scientific and Analytical
Number of Questions: 5

Reading Comprehension Passage

Read the following passage carefully and answer the questions that follow.

For centuries, scientists have attempted to organise the natural world into distinct categories. Species classification, once considered a relatively straightforward exercise based on physical similarities, has become increasingly complicated with advances in genetics. Modern discoveries suggest that the boundaries separating living organisms are neither as permanent nor as clearly defined as earlier scientists believed.

Traditionally, organisms were classified according to observable characteristics such as body structure, appearance and reproductive behaviour. This approach proved useful, but it occasionally produced misleading conclusions. Two organisms might look remarkably similar because they evolved under comparable environmental pressures rather than because they shared a recent common ancestor. Conversely, members of the same species could appear quite different due to variations in age, sex or geographical conditions.

Genetic analysis has transformed this understanding by allowing scientists to examine evolutionary relationships more directly. DNA comparisons sometimes reveal that organisms previously grouped together are genetically distant, while seemingly unrelated organisms possess significant evolutionary connections. However, genetics has not eliminated uncertainty. Different genetic markers may suggest different relationships, particularly when species have separated relatively recently or exchanged genetic material through interbreeding.

The classification of species also raises a deeper question: what exactly makes a species distinct? One influential definition identifies a species as a group of organisms capable of interbreeding and producing fertile offspring. Yet this definition becomes difficult to apply to organisms that reproduce asexually or to extinct species known only through fossils. Furthermore, some closely related animal species occasionally interbreed, producing hybrids that challenge rigid classifications.

Evolution itself contributes to this difficulty. Species do not emerge overnight through clearly identifiable transitions. Instead, populations gradually accumulate genetic differences over many generations. At what point these differences become sufficient to establish a new species is often a matter of scientific judgement. Nature rarely provides the precise dividing lines that human classification systems demand.

Nevertheless, these uncertainties do not render classification meaningless. Scientific categories remain essential for studying biodiversity, tracing evolutionary history and developing conservation strategies. Identifying genetically distinct populations, for instance, may help conservationists recognise vulnerable groups that would otherwise remain overlooked.

The real challenge, therefore, is not to abandon classification but to recognise its limitations. Scientific knowledge advances when established categories are treated as useful explanations rather than unquestionable truths. Genetics has not demonstrated that species are imaginary; instead, it has revealed that biological diversity is more complex than any single classification system can fully capture. The strength of science lies not in defending its existing boundaries indefinitely, but in its willingness to redraw them when evidence demands.

Multiple-Choice Questions

Q1. Which of the following best captures the central idea of the passage?

(A) Genetic research has established that traditional species classifications are scientifically unreliable and should be abandoned.

(B) The biological definition of species is primarily determined by the ability of organisms to produce fertile offspring.

(C) Advances in genetics have exposed the complexity of species classification, highlighting the need for scientific categories that remain open to revision.

(D) Evolutionary relationships can be accurately established only through genetic analysis rather than physical characteristics.

Q2. Which of the following can be most reasonably inferred from the passage?

(A) Two organisms with similar physical characteristics may not necessarily share a recent evolutionary ancestor.

(B) Organisms capable of interbreeding must always belong to the same species, regardless of their genetic differences.

(C) Genetic evidence has made physical characteristics irrelevant to the study of evolutionary relationships.

(D) Scientists generally disagree on whether evolution occurs gradually or through sudden biological transformations.

Q3. What does the author most likely mean by the statement, “Nature rarely provides the precise dividing lines that human classification systems demand”?

(A) Natural organisms cannot be meaningfully classified because their genetic structures constantly change.

(B) Human classification systems are fundamentally artificial and have no scientific relevance.

(C) Genetic differences between organisms are usually too insignificant to support meaningful distinctions.

(D) Evolutionary changes often occur gradually, making it difficult to identify exact boundaries between species.

Q4. Which of the following best describes the author’s attitude towards scientific classification?

(A) Sceptical and dismissive, because classification systems consistently misrepresent evolutionary relationships.

(B) Appreciative but critical, recognising the usefulness of classification while emphasising its limitations.

(C) Unreservedly supportive, because genetic advances have resolved the weaknesses of traditional classification.

(D) Indifferent, because the distinction between species has little practical importance for scientific research.

Q5. Which of the following conclusions is most strongly supported by the passage?

(A) Scientists should develop a universal genetic standard that permanently determines the identity of every species.

(B) Species classification should focus exclusively on conservation rather than on understanding evolutionary relationships.

(C) The reliability of scientific classification depends partly on its capacity to incorporate new evidence and revise established categories.

(D) The existence of hybrids demonstrates that biological species have no meaningful genetic or evolutionary distinctions.

Answer Key

Detailed Explanations

Q1. Correct Answer: (C)

The passage examines how advances in genetics have complicated the traditional understanding of species. While physical characteristics once formed the primary basis of classification, genetic evidence has revealed unexpected evolutionary relationships and blurred boundaries between certain species.

The author does not argue that classification should be discarded. Instead, the final paragraph emphasises that scientific categories must remain open to revision when new evidence emerges.

Therefore, Option (C) accurately reflects both the complexity of classification and the author’s argument for scientific flexibility.

Why the other options are incorrect:

• (A) is incorrect because the author explicitly states that classification remains essential despite its limitations.
• (B) describes only one definition of species discussed in the passage, rather than its central argument.
• (D) exaggerates the author’s position. Genetics provides valuable evidence but has not completely eliminated uncertainty or replaced every other method of classification.

Q2. Correct Answer: (A)

The second paragraph explains that organisms may develop similar physical features because they experience comparable environmental pressures, even when they do not share a recent common ancestor.

This supports the inference that physical resemblance does not necessarily establish a close evolutionary relationship.

Therefore, Option (A) is correct.

Why the other options are incorrect:

• (B) contradicts the discussion of hybridisation, which demonstrates that organisms classified as different species may occasionally interbreed.
• (C) is too extreme. The passage identifies limitations in traditional classification but does not suggest that physical characteristics have become irrelevant.
• (D) introduces a claim about scientific disagreement regarding the speed of evolution that the passage does not establish.

Q3. Correct Answer: (D)

The statement appears immediately after the author discusses how populations gradually accumulate genetic differences over generations.

Unlike human-made categories, which generally require clear distinctions, evolutionary change often takes place continuously. Consequently, identifying the exact moment when one population becomes a separate species can be difficult.

Option (D) best captures this meaning.

Why the other options are incorrect:

• (A) is incorrect because the author argues that classification remains meaningful.
• (B) overstates the criticism. The author considers classification useful, even if its boundaries are imperfect.
• (C) incorrectly assumes that genetic differences are generally insignificant. The passage discusses difficulties in determining when those differences justify recognising separate species, not whether meaningful differences exist.

Q4. Correct Answer: (B)

The author’s tone is balanced and analytical.

Throughout the passage, the author acknowledges the limitations of traditional classification, the uncertainties associated with genetic evidence and the challenges of defining species.

However, the author also recognises the importance of classification in biodiversity research, evolutionary studies and conservation.

This combination demonstrates an attitude that is appreciative of scientific classification while remaining critical of its limitations.

Therefore, Option (B) is correct.

Why the other options are incorrect:

• (A) misrepresents the author’s attitude as dismissive, although the passage defends the usefulness of classification.
• (C) is incorrect because the author specifically explains that genetics has not resolved all uncertainties.
• (D) contradicts the passage’s discussion of the practical importance of classification.

Q5. Correct Answer: (C)

The passage concludes by emphasising that scientific progress depends on the willingness to reconsider established categories when new evidence becomes available.

The author presents classification as a valuable scientific tool rather than a permanently fixed representation of nature.

Option (C) therefore follows directly from the concluding argument: scientific classification remains useful partly because it can adapt to improved knowledge.

Why the other options are incorrect:

• (A) contradicts the author’s emphasis on revisable categories. The passage does not support permanent or universally applicable genetic boundaries.
• (B) incorrectly restricts classification to conservation. The passage identifies evolutionary research and biodiversity studies as additional purposes.
• (D) exaggerates the implications of hybridisation. The existence of hybrids complicates species boundaries but does not establish that meaningful biological distinctions are absent.