The forelimb of male frog is distinct from female frog due to the presence of

Options

A. Forearm
B. Thumb
C. Web
D. Copulatory pad

Explanation

**Step-by-Step Solution:**

1. **Identify the Distinct Features**: The forelimb of male frogs is distinct from that of female frogs due to specific anatomical features.

2. **Vocal Sac**: One of the key distinguishing features of male frogs is the presence of a vocal sac. This is a loose fold of skin located on the throat area of male frogs, which is not present in females. The vocal sac is used during mating calls.

3. **Copulatory Pad**: Another significant feature is the presence of the copulatory pad on the forelimb of male frogs. This pad is located on the first digit (thumb) of the forelimb and is used to grasp the female during mating.

4. **Understanding Amphylexis**: The copulatory pad plays a crucial role during the mating process known as amphylexis, where the male frog holds onto the female tightly to facilitate reproduction.

5. **Conclusion**: The distinct feature of the forelimb in male frogs, which differentiates them from female frogs, is the presence of the copulatory pad.

**Final Answer**: The forelimb of male frogs is distinct from female frogs due to the presence of the copulatory pad.

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