Iodine is necessary for the synthesis of one of the following hormones. This hormone is :

Options

A. adrenaline
B. auxin
C. insulin
D. thyroxin

Answer

To solve the question regarding which hormone requires iodine for its synthesis, we can follow these steps:

### Step 1: Identify the hormones listed
The question provides four options:
1. Adenoline
2. Oxen
3. Insulin
4. Thyroxine

### Step 2: Understand the role of iodine
Iodine is an essential nutrient that plays a crucial role in the synthesis of certain hormones in the body.

### Step 3: Analyze each hormone
- **Adenoline**: This hormone is associated with the adrenal glands and is involved in the body's response to stress. It does not require iodine for its synthesis.
- **Oxen**: This is a plant hormone that regulates growth and development in plants. It is not related to iodine.
- **Insulin**: This hormone is produced by the pancreas and regulates blood glucose levels. It does not require iodine for its synthesis.
- **Thyroxine**: This hormone is produced by the thyroid gland and is known to require iodine for its synthesis.

### Step 4: Conclude the answer
Based on the analysis, the hormone that requires iodine for its synthesis is **Thyroxine**.

### Final Answer:
The hormone that requires iodine for its synthesis is **Thyroxine**.

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