Assertion : Accommodation power is present in human eye but absent in frog eye.
Reason : Iridial muscles are present in human eye but are absent in frog eye.

Options

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

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Accommodation power is present in the human eye but absent in the frog eye."
- Accommodation power refers to the ability of the eye to change its focal length to focus on objects at different distances. In humans, the lens can change shape due to the action of ciliary muscles, allowing us to see both near and far objects clearly.

2. **Understanding the Reason**:
- The reason states that "Iridial muscles are present in the human eye but are absent in the frog eye."
- Iridial muscles are responsible for controlling the size of the pupil, thus regulating the amount of light entering the eye. However, the presence of iridial muscles is not directly related to the accommodation power of the lens.

3. **Evaluating the Truth of Each Statement**:
- The assertion is **true** because humans have accommodation power, while frogs do not have the same level of accommodation due to the structure of their eyes.
- The reason is **false** because iridial muscles are indeed present in both human and frog eyes. Therefore, the reason does not correctly explain the assertion.

4. **Conclusion**:
- Since the assertion is true and the reason is false, the correct answer is that the assertion is true, but the reason is false.

### Final Answer:
The correct option is: **Assertion is true and Reason is false.**

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