........... are present only in plant cell.

Options

A. Plastids
B. Animal cell
C. Both of these
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks for what is present only in plant cells.

2. **Consider the Options:** The options provided include:
- Plastids
- Animal cells
- Both of these
- None of these

3. **Analyze Each Option:**
- **Plastids:** These are organelles found only in plant cells. They are responsible for functions such as photosynthesis (in chloroplasts), storage (in leucoplasts), and pigment synthesis (in chromoplasts).
- **Animal Cells:** This option is incorrect because animal cells do not contain plastids.
- **Both of These:** This option is incorrect as well since plastids are not found in animal cells.
- **None of These:** This option is also incorrect because plastids are indeed present in plant cells.

4. **Conclusion:** The only correct answer is "Plastids," as they are exclusively found in plant cells.

**Final Answer:** Plastids are present only in plant cells.

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