[A]: Mimics are always or more often defenceless.
[R]: Mimics are always less in number than the model individuals

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 (A)**: The assertion states that "Mimics are always or more often defenseless." This implies that mimics, which are organisms that imitate other organisms (models), lack defenses against predators.

2. **Understanding the Reason (R)**: The reason states that "Mimics are always less in number than the model individuals." This suggests that mimics are fewer in number compared to the organisms they imitate.

3. **Defining Mimicry**: Mimicry is an evolved mechanism where one organism (the mimic) resembles another (the model) that is not closely related. This resemblance often serves a purpose, such as protection from predators.

4. **Analyzing the Relationship Between A and R**:
- The assertion (A) suggests that mimics are defenseless, which can be true in certain cases (like in the case of some harmful models).
- The reason (R) states that mimics are always less in number than models. However, this is not universally true; mimics can be equal to or greater in number than models in some cases.

5. **Conclusion**:
- The assertion (A) can be true in specific contexts, particularly in cases of mimicry where the mimics are indeed defenseless.
- The reason (R) is not universally true, as mimics can sometimes be equal to or greater in number than their models.
- Therefore, the assertion is true, but the reason is false. The reason does not correctly explain the assertion.

6. **Final Answer**: A is true, and R is false.

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