From recent studies, it has been found that pre-existing plastids arise from

Options

A. Bodies called proplastids
B. The nucleus
C. The vacuole
D. The cell wall

Explanation

To answer the question "From recent studies, it has been found that pre-existing plastids arise from," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking about the origin of pre-existing plastids in plant cells.

2. **Identify the Options**: The options provided are:
- A) Proplastids
- B) Nucleus
- C) Vacuole
- D) Cell wall

3. **Research on Plastids**: Plastids are organelles found in plant cells that are involved in the synthesis and storage of food. They include chloroplasts, chromoplasts, and leucoplasts.

4. **Learn about Proplastids**: Proplastids are the precursor organelles from which plastids develop. They are found in the meristematic regions of plants, which are areas of active cell division.

5. **Connect the Information**: Since plastids develop from proplastids, we can conclude that pre-existing plastids arise from proplastids.

6. **Select the Correct Option**: Based on the information gathered, the correct answer is:
- A) Proplastids

### Final Answer:
Pre-existing plastids arise from bodies called proplastids.

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