Which of the following endocrine glands is unpaired?

Options

A. Adrenal
B. Testes
C. Pituitary
D. Ovary

Explanation

To determine which of the following endocrine glands is unpaired, we can analyze the given options one by one:

1. **Adrenal Glands**:
- There are two adrenal glands, one located on top of each kidney. Therefore, they are paired.

2. **Testis**:
- In males, there are two testes, which are also paired structures. They are located outside the abdominal cavity and are responsible for sperm formation and testosterone secretion.

3. **Pituitary Gland**:
- The pituitary gland is located just below the brain. It is considered an unpaired gland because there is only one pituitary gland in the human body. It plays a crucial role in hormone secretion, including growth hormone, and is often referred to as the "master gland."

4. **Ovaries**:
- In females, there are two ovaries, which are paired structures. They are involved in the formation of ova and the secretion of estrogen.

Based on this analysis, the only unpaired endocrine gland among the options provided is the **pituitary gland**.

### Final Answer:
The unpaired endocrine gland is the **pituitary gland**.

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