Assertion (A): Big bang theory says that the universe is still expanding.
Reason (R): The expansion of the universe caused the decrease in temperature.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.

Subtopic:  Cosmic Evolution |
 54%
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Assertion (A): According to Darwin, fitness means reproductive fitness.
Reason (R): Those who are a better fit in the environment will leave more progenies.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Darwin's Theory | Summary of Darwin's Theory | Modern Theory of Evolution |
 87%
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Assertion (A): The new forms of life have arisen at different times in the history of the earth.
Reason (R): Studies showed that life forms varied over time and certain life forms are restricted to certain geological timespans.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Concept of Organic Evolution: Evidence |
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Assertion (A): In convergent evolution, the same structure developed in animals along different directions due to adaptations to different needs.
Reason (R): Homologous structures have similar anatomy but perform different functions.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Concept of Organic Evolution: Evidence |
 65%
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Assertion (A): In polluted environments, melanic moths were more selected by nature.
Reason (R): Melanic moths were able to camouflage themselves during industrialization.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Concept of Isolation | Concept of Speciation | Genetic Basis of Adaptation |
 88%
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Assertion (A): The resistant organisms/cells appear over a time scale of centuries.
Reason (R): Excess use of antibiotics has resulted in the selection of resistant varieties.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Natural Selection | Concept of Speciation | Genetic Basis of Adaptation |
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Assertion (A): There must be a genetic basis for getting selected and evolving.
Reason (R): Adaptive ability is inherited.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Concept of Speciation | Genetic Basis of Adaptation |
 59%
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Assertion (A): As per Darwin, over many generations, survivors will leave more progenies.
Reason (R): Survivors have variations that make resource utilization better for them.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Theory of Evolution & Lamarckism | Darwin's Theory | Summary of Darwin's Theory | Modern Theory of Evolution |
 83%
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Assertion (A): deVries believed that mutation caused speciation.
Reason (R): The mutation causing speciation is known as saltation as per Darwin.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Genetic Basis of Adaptation |
 75%
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Assertion (A): The probability of genotype Aa is 2pq in the Hardy-Weinberg population.
Reason (R): Hardy-Weinberg equilibrium, p2 +2pq+q2=1.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. (A) is true, but (R) is false.
4. (A) is false, but (R) is true.
Subtopic:  Hardy Weinberg Law |
 53%
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