Triploid tissue in angiosperm is

Options

A. Nucellus
B. Endosperm
C. Endothecium
D. Tapetum

Explanation

### Step-by-Step Solution:

1. **Understanding the Context**: The question asks about triploid tissue in angiosperms. To answer this, we need to recall the process of fertilization in flowering plants, particularly focusing on the concept of double fertilization.

2. **Double Fertilization**: In angiosperms, double fertilization occurs when one male gamete fuses with the egg cell to form a diploid zygote, while the other male gamete fuses with two polar nuclei in the ovule to form the endosperm.

3. **Formation of Endosperm**: The fusion of the second male gamete (haploid) with the two polar nuclei (which are also haploid) results in a triploid (3n) structure known as the primary endosperm nucleus (PEN). This PEN eventually develops into the endosperm, which serves as a nutrient source for the developing embryo.

4. **Identifying the Triploid Tissue**: Since the endosperm is formed from the fusion of one haploid male gamete with two haploid polar nuclei, it is classified as triploid tissue (3n).

5. **Conclusion**: Therefore, the correct answer to the question "Triploid tissue in angiosperm is" is **endosperm**.

### Final Answer:
The triploid tissue in angiosperm is **endosperm**.

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