Organ of mastication in cockroach is

Options

A. Mandibles
B. Maxilla
C. Labium
D. Labrum.

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the organ of mastication in a cockroach.

2. **Understand the Options**: The options provided are:
- Option 1: Mandible
- Option 2: Maxilla
- Option 3: Labium
- Option 4: Labrum

3. **Define Mastication**: Mastication refers to the process of chewing food. It involves breaking down food into smaller pieces to facilitate digestion.

4. **Role of Different Mouthparts**:
- **Mandible**: The mandibles are the primary chewing organs in cockroaches. They are responsible for biting and grinding food.
- **Maxilla**: The maxillae help in manipulating food and bringing it to the mandibles but do not directly chew the food.
- **Labium**: The labium acts like a lip, helping to hold the food in place during mastication.
- **Labrum**: The labrum also functions similarly to the labium, assisting in keeping the food from falling out.

5. **Conclusion**: Since the question specifically asks for the organ responsible for mastication, the correct answer is the **mandible**.

6. **Final Answer**: The organ of mastication in a cockroach is the **mandible** (Option 1).