Thalamus is

Options

A. Base of flower
B. Base of ovary
C. Modification of pollen
D. Modification of petal

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the thalamus and its definition or identification among the given options.

2. **Analyzing the Options**: The options provided are:
- A) Base of flower
- B) Base of ovary
- C) Modification of pollen
- D) Modification of petal

3. **Identifying the Correct Definition**:
- The thalamus, also known as the receptacle, is the part of the flower that is located at the base. It supports the other floral parts (like petals, sepals, stamens, and carpels) and is crucial in the structure of the flower.

4. **Evaluating Each Option**:
- **Base of flower**: This is correct as the thalamus is indeed the receptacle at the base of the flower.
- **Base of ovary**: Incorrect, as the ovary is a part of the flower but is not synonymous with thalamus.
- **Modification of pollen**: Incorrect, as pollen refers to the male gametophytes and is not related to the thalamus.
- **Modification of petal**: Incorrect, as petals are part of the flower structure but do not define the thalamus.

5. **Conclusion**: The correct answer is A) Base of flower, as it accurately describes the thalamus.

**Final Answer**: Thalamus is the base of the flower.

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