Which of these structures has two sets of chromosomes in flowering plants?
(a) Microspore
(b) Microsporangium
(c) Endosperm
(d) Megaspore

Options

A. Microspore
B. Microsporangium
C. Endosperm
D. Megaspore

Answer

To solve the question of which structure has two sets of chromosomes in flowering plants, we need to analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Chromosome Sets**:
- In flowering plants, organisms can have different sets of chromosomes:
- **Diploid (2n)**: Two sets of chromosomes.
- **Haploid (n)**: One set of chromosomes.
- **Triploid (3n)**: Three sets of chromosomes.

2. **Analyzing Each Option**:
- **(a) Microspore**:
- Microspores are the male gametes (pollen grains) and are haploid (n). Therefore, they have only one set of chromosomes.
- **Conclusion**: Not the correct option.

- **(b) Microsporangium**:
- Microsporangium is the structure where microspores are produced. It is diploid (2n) because it contains two sets of chromosomes.
- **Conclusion**: This is the correct option.

- **(c) Endosperm**:
- The endosperm is a tissue that provides nourishment to the developing embryo and is typically triploid (3n), meaning it has three sets of chromosomes.
- **Conclusion**: Not the correct option.

- **(d) Megaspore**:
- Megaspores are involved in the formation of the female gametes and are haploid (n), meaning they have only one set of chromosomes.
- **Conclusion**: Not the correct option.

3. **Final Answer**:
- Based on the analysis, the structure that has two sets of chromosomes in flowering plants is **(b) Microsporangium**.