Which of the following is haploid ?

Options

A. Style
B. Ovary
C. Synergids
D. Primary endosperm nucleus

Answer

To determine which of the given options is haploid, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Haploid and Diploid**:
- Haploid cells contain one set of chromosomes (n).
- Diploid cells contain two sets of chromosomes (2n).

2. **Analyzing the Options**:
- **Style**: The style is part of the female reproductive structure of a flower. It is made up of diploid cells, as it is derived from the ovary which is diploid. Therefore, the style is **not haploid**.
- **Ovary**: The ovary is also part of the female reproductive structure and contains diploid cells. It develops into the fruit after fertilization. Thus, the ovary is **not haploid**.
- **Synergids**: Synergids are specialized cells located near the egg cell in the embryo sac of the ovule. They are formed from the megaspore and contain a haploid set of chromosomes. Therefore, synergids are **haploid**.
- **Primary Endosperm Nucleus**: The primary endosperm nucleus is formed after the fertilization of the central cell by a male gamete. It is triploid (3n) because it results from the fusion of one male gamete with two polar nuclei. Thus, the primary endosperm nucleus is **not haploid**.

3. **Conclusion**:
- Among the given options, the only haploid structure is the **synergids**.

### Final Answer:
The correct answer is **synergids**.

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