Vocal sacs are found in:-

Options

A. male frog
B. female frog
C. both
D. none

Answer

**Step-by-Step Solution:**

1. **Understanding Vocal Sacs**: Vocal sacs are specialized structures found in certain animals that help in sound production. They are particularly important for mating calls.

2. **Identifying the Species**: In the context of frogs, vocal sacs are primarily associated with males. These sacs are used to amplify their calls to attract females during mating.

3. **Function of Vocal Sacs**: The vocal sacs are made of flexible skin, which allows them to expand and contract. This flexibility enables the male frog to change the frequency of the sound waves produced, enhancing the volume and clarity of the mating call.

4. **Mechanism of Sound Production**: When a male frog wants to call a female, it inflates its lungs and closes its mouth and nostrils. This action forces air through the vocal sacs, producing a loud call that can travel long distances.

5. **Sex Determination**: The presence of vocal sacs is often used as an external characteristic to determine the sex of the frog. In many species, only male frogs develop these vocal sacs.

6. **Conclusion**: Based on the information provided, vocal sacs are found in male frogs.

**Final Answer**: Vocal sacs are found in male frogs.

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