An organelle with an internal cross-section showing characteristic ''9+2'' array is the

Options

A. (a) microtubule
B. (b) microfilament
C. (c) cilium or flagellum
D. (d) cytoskeleton

Explanation

To solve the question about which organelle has an internal cross-section showing a characteristic "9+2" array, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for an organelle that displays a "9+2" arrangement in its internal structure. This arrangement is commonly associated with certain cellular structures.

2. **Identifying the Structures**: The options provided are:
- A) Microtubule
- B) Microfilament
- C) Coelom or Flagellum
- D) Cytoskeleton

3. **Analyzing the Options**:
- **Microtubule**: While microtubules are part of the cytoskeleton and can be involved in various cellular functions, they do not specifically refer to the "9+2" arrangement.
- **Microfilament**: Microfilaments are thin filaments involved in cell movement and shape but do not exhibit the "9+2" structure.
- **Coelom or Flagellum**: These structures are known for their role in movement and are characterized by the "9+2" arrangement of microtubules in their axoneme (the central shaft).
- **Cytoskeleton**: This term encompasses various structures within the cell, including microtubules and microfilaments, but does not specifically refer to the "9+2" arrangement.

4. **Confirming the Correct Answer**: The "9+2" arrangement refers specifically to the structure found in the axoneme of cilia and flagella, which consists of 9 pairs of peripheral microtubules and 2 central microtubules. Therefore, the correct answer is **C) Coelom or Flagellum**.

5. **Final Statement**: The organelle with an internal cross-section showing the characteristic "9+2" array is the **coelom or flagellum**.