Centrioles duplicate in the

Options

A. Nucleus
B. Endoplasmic reticulum
C. Cytoplasm
D. Mitochondria

Answer

### Step-by-Step Solution:

1. **Understanding Centrioles**: Centrioles are cylindrical, barrel-shaped organelles found in animal cells. They play a crucial role in cell division.

2. **Location of Centrioles**: Centrioles are located in the cytoplasm of animal cells, specifically near the nuclear envelope.

3. **Function of Centrioles**: The primary function of centrioles is to assist in cell division by forming spindle fibers. These spindle fibers are essential for separating sister chromatids during cell division.

4. **Cell Cycle Phase**: Centrioles are particularly important during the M-phase (mitotic phase) of the cell cycle. They are involved in the formation of spindle fibers during metaphase and anaphase.

5. **Duplication of Centrioles**: The duplication of centrioles occurs during the interphase, which is the phase before the M-phase. This duplication takes place in the cytoplasm, where the centrioles are located.

6. **Conclusion**: Therefore, the correct answer to the question "Centrioles duplicate in the" is **cytoplasm**.

### Final Answer:
Centrioles duplicate in the **cytoplasm**.

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