Select the correct option regarding the ploidy level of different structures of an angiospermous ovule.

Options

A. `{:("Nucellus",MMC,"Functional megaspore"),(n,2n,2n):}`
B. `{:("Nucellus",MMC,"Functional megaspore"),(2n,n,n):}`
C. `{:("Nucellus",MMC,"Functional megaspore"),(2n,2n,n):}`
D. `{:("Nucellus",MMC,"Functional megaspore"),(n,2n,n):}`

Explanation

To determine the correct option regarding the ploidy level of different structures of an angiospermous ovule, we need to analyze the various components of the ovule and their respective ploidy levels. Here’s a step-by-step solution:

### Step 1: Understand the Structures of the Ovule
The ovule consists of several key structures, including the nucellus, megasporangium (which contains the megasporangial mother cell), and the embryo sac.

### Step 2: Identify the Ploidy Levels
1. **Nucellus**: The nucellus is the tissue surrounding the embryo sac. It is made up of parenchyma cells, which are diploid (2n).

2. **Megasporangium (Megaspore Mother Cell)**: This cell is also diploid (2n). It undergoes meiosis to produce megaspores.

3. **Megaspores**: The megasporangium undergoes meiosis to produce four megaspores, but typically only one of these megaspores is functional, while the others are non-functional. The functional megaspore is haploid (n).

### Step 3: Summarize the Ploidy Levels
- **Nucellus**: Diploid (2n)
- **Megaspore Mother Cell**: Diploid (2n)
- **Functional Megaspore**: Haploid (n)

### Step 4: Select the Correct Option
Based on the analysis, the correct option regarding the ploidy levels of the structures in an angiospermous ovule is:
- Nucellus: Diploid (2n)
- Megasporangium (Megaspore Mother Cell): Diploid (2n)
- Functional Megaspore: Haploid (n)

Thus, the correct option is that the nucellus is diploid, the megasporangium is diploid, and the functional megaspore is haploid.