Question

Assertion (A): The earliest organisms that appeared on the earth were non-green and anaerobes.

Reason (R): The first autotrophic organisms were chemoautotrophs that did not release oxygen.

Options

• Both assertion (A) and reason (R) are true, and reason is the correct explanation of assertion.

• Both assertion (A) and reason (R) are true, but reason is not the correct explanation of assertion.

• Assertion (A) is true but reason (R) is false.

• Both assertion (A) and reason (R) are false.

Answer 1

Both assertion (A) and reason (R) are true, but reason is not the correct explanation of assertion.

Explanation:

The earliest organisms are considered non-green and anaerobic because free oxygen was absent and they relied on available organic compounds. The proposed early chemoautotrophs did not release oxygen, but that fact does not explain why the earliest organisms were anaerobes.