Insufficient production of ____ in the tadpoles leads to their incomplete development.

Options

A. thyroxin
B. insulin
C. nutrients
D. ducts

Explanation

To answer the question, "Insufficient production of ____ in the tadpoles leads to their incomplete development," we need to identify the hormone that is crucial for the development of tadpoles.

### Step-by-Step Solution:

1. **Understanding Tadpole Development**:
- Tadpoles are the larval stage of frogs and undergo significant changes as they develop into adult frogs. This process is known as metamorphosis.

2. **Identifying Key Hormones**:
- The development of tadpoles is regulated by hormones. The most important hormone for their metamorphosis is Thyroxine.

3. **Role of Thyroxine**:
- Thyroxine is produced by the thyroid gland and plays a critical role in regulating metabolism and growth. In tadpoles, it is essential for the transition from the tadpole stage to the adult frog stage.

4. **Consequences of Insufficient Thyroxine**:
- If there is insufficient production of Thyroxine, it can lead to incomplete metamorphosis. This means that the tadpoles may not develop properly, potentially resulting in stunted growth or failure to develop legs and lose their tails.

5. **Conclusion**:
- Therefore, the answer to the question is "Thyroxine." Insufficient production of Thyroxine in tadpoles leads to their incomplete development.

### Final Answer:
Insufficient production of **Thyroxine** in the tadpoles leads to their incomplete development.

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