Assertion (A) >: The first living organisms evolved on the earth were Chemo-hetero- trophs. Reason (R) > : At the time of evolution of first living organisms on earth, there was no molecular oxygen

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Q: 42 (IES/2004)

Assertion (A): The first living organisms evolved on the earth were Chemo-hetero- trophs.
Reason (R) : At the time of evolution of first living organisms on earth, there was no molecular oxygen

question_subject: 

Science

question_exam: 

IES

stats: 

0,1,18,15,1,2,1

keywords: 

{'first living organisms': [0, 0, 1, 0], 'evolution': [1, 0, 1, 0], 'organisms': [4, 1, 3, 2], 'molecular oxygen': [0, 0, 1, 0], 'chemo': [0, 0, 1, 0], 'earth': [0, 1, 1, 1], 'correct explanatioin': [1, 0, 2, 0]}

Option 1 states that both the Assertion (A) and Reason (R) are true, and that R is the correct explanation of A. This means that the first living organisms evolved on Earth were Chemo-heterotrophs and the reason for this is because at that time, there was no molecular oxygen.

Option 2 states that both the Assertion (A) and Reason (R) are true, but R is not a correct explanation of A. This means that while the first living organisms evolved on Earth were Chemo-heterotrophs, the absence of molecular oxygen is not the reason for this.

Option 3 states that A is true, but R is false. This means that the first living organisms evolved on Earth were Chemo-heterotrophs, but the reason for this is not because of the absence of molecular oxygen.

Option 4 states that A is false, but R is true. This means that the first living organisms evolved on Earth were not Chemo-heterotrophs, but it is true that there was no molecular oxygen at that time.

Based on the provided information, the correct answer is option 2, where both A and R are true but R is not a correct explanation of A.