Lower jaw is toothless in

Options

A. Cockroach
B. Frog
C. rabbit
D. None of these

Answer

To determine which organism has a toothless lower jaw, we will analyze each option provided in the question: cockroach, frog, rabbit, and none of these.

### Step-by-Step Solution:

1. **Understanding the Question**: We need to identify which of the given animals has a lower jaw that does not have teeth.

2. **Analyzing the Options**:
- **Cockroach**: Cockroaches have a gizzard where they possess teeth-like structures for grinding food. Therefore, the lower jaw of a cockroach is not toothless.
- **Frog**: Frogs have a unique dental structure. Their lower jaw is indeed toothless. They have teeth known as acrodont, which are located on the upper jaw and are used primarily for holding prey, not for chewing.
- **Rabbit**: Rabbits have a complete set of teeth, including a lower jaw with incisors and molars. Therefore, the rabbit is not toothless.
- **None of these**: This option implies that none of the listed animals are toothless, which is incorrect since we have identified that frogs are toothless in the lower jaw.

3. **Conclusion**: Based on the analysis, the correct answer is **Frog** (option B), as it has a toothless lower jaw.

### Final Answer:
The lower jaw is toothless in **Frog**.

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