Which of the following hormone helps in maintaining body temperature, metabolism, pigmentation, and defense capabilities?

Options

A. Melatonin
B. Melanin
C. Thymosis
D. Calcitonin

Answer

To solve the question regarding which hormone helps in maintaining body temperature, metabolism, pigmentation, and defense capabilities, we can follow these steps:

### Step 1: Identify the Functions Mentioned
The question specifies four functions:
1. Maintaining body temperature
2. Metabolism
3. Pigmentation
4. Defense capabilities

### Step 2: Analyze the Hormones Listed
We need to consider the hormones that are commonly known and see which one aligns with the functions mentioned. The options provided are:
- Melatonin
- Melanin
- Thymosin
- Calcitonin

### Step 3: Evaluate Each Option
1. **Melatonin**: This hormone is secreted by the pineal gland and is known for regulating sleep-wake cycles, but it also plays a role in body temperature regulation, metabolism, and has effects on pigmentation and immune defense.

2. **Melanin**: This is not a hormone but a pigment responsible for skin color. Therefore, it does not fit the criteria of the question.

3. **Thymosin**: This hormone is secreted by the thymus gland and is primarily involved in the immune response, but it does not regulate body temperature or metabolism.

4. **Calcitonin**: This hormone helps in the regulation of calcium metabolism but does not have a role in body temperature, pigmentation, or defense capabilities.

### Step 4: Conclusion
Based on the analysis, the hormone that helps in maintaining body temperature, metabolism, pigmentation, and defense capabilities is **Melatonin**.

### Final Answer
The correct answer is **Melatonin**.

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