Hyposecretion of which hormone is responsible for cretinism?

Options

A. Thyroxine
B. Parathormone
C. Growth Hormone
D. Calcitonin

Answer

**Step-by-Step Solution:**

1. **Understanding Cretinism**: Cretinism is a condition characterized by physical deformities and mental retardation. It is primarily caused by a deficiency in certain hormones during development.

2. **Identifying Hormones**: The question asks about the hyposecretion (or underproduction) of a specific hormone. The options provided are:
- A) Thyroxin
- B) Parathormone
- C) Growth Hormone
- D) Calcitonin

3. **Analyzing the Options**:
- **Thyroxin**: This is a thyroid hormone (also known as T4) that plays a crucial role in regulating metabolism. A deficiency in thyroxin can lead to decreased metabolism, which is associated with symptoms of cretinism.
- **Parathormone**: This hormone regulates calcium levels in the blood and is not directly linked to cretinism.
- **Growth Hormone**: While a deficiency in growth hormone can lead to dwarfism, it does not cause the mental retardation seen in cretinism.
- **Calcitonin**: This hormone also regulates calcium levels and does not have a direct link to cretinism.

4. **Conclusion**: Given the analysis, the hormone whose hyposecretion is responsible for cretinism is **Thyroxin (Option A)**. A lack of thyroxin leads to low metabolism, which is a key factor in the development of cretinism.

**Final Answer**: The hyposecretion of **Thyroxin** is responsible for cretinism.

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