The structure that forms most of the flesh of an apple is the :

Options

A. pistil
B. receptacle
C. petal
D. stamen

Explanation

To answer the question "The structure that forms most of the flesh of an apple is the:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking about the structure that constitutes the majority of the flesh of an apple.

2. **Identify the Options**: The options provided are:
- A) Pistil
- B) Receptacle
- C) Petal
- D) Stem

3. **Analyze Each Option**:
- **Pistil**: This is the female reproductive part of the flower, which includes the ovary, style, and stigma. It is responsible for receiving pollen but does not form the flesh of the fruit.
- **Receptacle**: This is the thickened part of the stem from which the flower organs arise. In the case of an apple, the flesh is primarily derived from the receptacle.
- **Petal**: Petals are the colorful parts of flowers that attract pollinators. They do not contribute to the fleshy part of the fruit.
- **Stem**: The stem supports the plant and transports nutrients but does not form the flesh of the fruit.

4. **Conclusion**: Since the apple is classified as a false fruit (pseudocarp), it develops mainly from the receptacle rather than the ovary. Therefore, the structure that forms most of the flesh of an apple is the **receptacle** (Option B).

5. **Final Answer**: The correct answer is **B) Receptacle**.