"Brain sand" is found in :

Options

A. Thyroid
B. Thymus
C. Pineal body
D. All

Answer

**Step-by-Step Solution:**

1. **Identify the Options**: The question asks where "brain sand" is found, with the options being thyroid, thymus, pineal body, and possibly others.

2. **Understand "Brain Sand"**: "Brain sand" refers to calcified structures that can be found in certain parts of the brain. It is important to know which part of the brain contains these structures.

3. **Locate the Pineal Gland**: The pineal gland is located on the dorsal side of the forebrain. It is a small endocrine gland that plays a role in the regulation of various biological rhythms.

4. **Confirm the Presence of Brain Sand**: Brain sand, also known as "corpora arenacea," is specifically found in the pineal gland. This is a key point in answering the question.

5. **Review Other Options**: The thyroid gland is the largest endocrine gland, and the thymus gland is involved in immune function. Neither of these glands is known to contain brain sand.

6. **Conclude the Answer**: Based on the information gathered, the correct answer to the question is that "brain sand" is found in the pineal body.

**Final Answer**: "Brain sand" is found in the pineal body.

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