Which is the structure act as sound receptor in cockroach :-

Options

A. Anal style
B. Anal cerci
C. Antenna
D. Both (2) and (3)

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the structure that acts as a sound receptor in cockroaches.

2. **Understand the Options**: The options given are:
- NL style
- NL Circe
- Antenna
- Both 2 and 3

3. **Analyze the Structures**:
- **NL Style**: This is a structure found in male cockroaches that serves as a copulatory organ, not a sound receptor.
- **NL Circe**: This refers to the structure known as "annulcersi," which are located on the 10th segment of both male and female cockroaches. These structures are believed to function as sound receptors.
- **Antenna**: While antennas are sensory organs, they are primarily involved in detecting chemicals and touch rather than sound.

4. **Determine the Correct Answer**: Based on the analysis, the structure that acts as a sound receptor in cockroaches is the **annulcersi** (NL Circe).

5. **Final Answer**: The correct option is **NL Circe**.