Pituitary gland is under the control of

Options

A. Thyroid gland
B. Adrenal gland
C. Adrenal medulla
D. Hypothalamus.

Answer

### Step-by-Step Solution:

1. **Understanding the Pituitary Gland**: The pituitary gland is often referred to as the "master gland" of the endocrine system because it regulates the functions of other endocrine glands in the body.

2. **Analyzing the Options**: The question provides four options regarding which gland controls the pituitary gland:
- **Option 1: Thyroid Gland**: Located between the trachea and larynx, it secretes thyroxin but does not control the pituitary gland.
- **Option 2: Adrenal Gland**: Found on top of the kidneys, it has two parts (cortex and medulla) and secretes various hormones but does not control the pituitary gland.
- **Option 3: Adrenal Medulla**: This is a part of the adrenal gland that secretes adrenaline and noradrenaline but does not control the pituitary gland.
- **Option 4: Hypothalamus**: Located in the forebrain, it regulates the synthesis and secretion of hormones from the pituitary gland.

3. **Identifying the Correct Answer**: Among the options, the hypothalamus is the only structure that controls the pituitary gland by regulating its hormone synthesis and secretion.

4. **Conclusion**: Therefore, the pituitary gland is under the control of the hypothalamus.

### Final Answer:
The pituitary gland is under the control of the **hypothalamus** (Option 4).

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