Tigellum is

Options

A. Testa
B. Tegmen
C. Both of the above
D. Main axis of the embryo

Answer

**Step-by-Step Solution:**

1. **Understanding Tigellum**: The tigellum is a term used in botany to refer to a specific part of the seed embryo. It is essential to identify what it represents in the context of plant reproduction.

2. **Identifying the Options**: The question provides four options:
- (a) Testa
- (b) Tegumen
- (c) Both of the above
- (d) Main axis of the embryo

3. **Analyzing the Options**:
- **Testa**: This is the outer protective covering of the seed. It does not relate to the structure of the embryo itself.
- **Tegumen**: This refers to the delicate inner protective layer of the seed. Again, it does not represent the main axis of the embryo.
- **Both of the above**: Since neither the testa nor the tegumen refers to the main axis of the embryo, this option is incorrect.
- **Main axis of the embryo**: This is the correct definition of the tigellum.

4. **Conclusion**: Based on the analysis, the tigellum is indeed the main axis of the embryo, which is the correct answer.

5. **Final Answer**: The correct answer is (d) Main axis of the embryo.

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