[A]: In large groups of animals and plants, there are identical enzymes and hormones available.
[R]: This suggests organic evolution

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that in large groups of animals and plants, there are identical enzymes and hormones available. This suggests a commonality in biochemical processes across diverse species.

2. **Identifying the Reason**: The reason given is that this situation suggests organic evolution. Organic evolution refers to the process by which different kinds of living organisms develop and diversify from earlier forms during the history of the earth.

3. **Linking Assertion and Reason**: The presence of identical enzymes and hormones in various species indicates that these organisms may have evolved from a common ancestor. This is a key concept in organic evolution, which posits that similarities in biochemical processes are due to shared ancestry.

4. **Examples of Organic Evolution**: To illustrate this point, consider the example of the frog and its evolutionary link to fish. Both share similar biochemical traits, such as certain enzymes and hormones, due to their common ancestry. The frog evolved from a fish-like ancestor, showcasing how modifications over generations lead to the current forms of life.

5. **Conclusion**: Since both the assertion and the reason are true, and the reason effectively explains the assertion, we can conclude that the correct answer is that both [A] and [R] are true, with [R] being the correct explanation for [A].

**Final Answer**: Both [A] and [R] are true, and [R] is the correct explanation for [A].

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