Which of the following gland is located on the dorsal side of the heart and aorta?

Options

A. Adrenal gland
B. Parathyroid gland
C. Thyroid gland
D. Thymus

Answer

To solve the question regarding which gland is located on the dorsal side of the heart and aorta, we can follow these steps:

### Step 1: Understand the Question
The question asks for the gland that is situated on the dorsal (back) side of the heart and aorta.

### Step 2: Analyze the Options
We have four options to consider:
1. Adrenal gland
2. Parathyroid gland
3. Thyroid gland
4. Thymus gland

### Step 3: Locate Each Gland
- **Adrenal Gland**: Located above the kidneys, not near the heart or aorta.
- **Parathyroid Gland**: Situated within the thyroid gland, which is in the neck region.
- **Thyroid Gland**: Located in the neck, not on the dorsal side of the heart or aorta.
- **Thymus Gland**: A small triangular gland located on the dorsal side of the heart and aorta.

### Step 4: Identify the Correct Answer
From the analysis, the thymus gland is the only gland that is located on the dorsal side of the heart and aorta.

### Conclusion
The correct answer is the **Thymus gland**.

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