Structures which help in distinguishing a male cockroach from a female cockroach are
(a) Anal styles
(b) Anal cerci
(c) Collateral glands
(d) Ocelli

Options

A. Anal Siyles
B. Anal cerci
C. Colleterial glands
D. Ocelli

Answer

To determine the structures that help in distinguishing a male cockroach from a female cockroach, we can analyze the given options based on the characteristics of both sexes.

### Step-by-Step Solution:

1. **Understanding the Characteristics of Male and Female Cockroaches**:
- Male cockroaches are generally smaller than females.
- The abdomen of the female cockroach is boat-shaped and blunt at the end, while the male's abdomen is more elongated.
- The wings of males extend to the tip of the abdomen, while females have shorter wings.
- Males have larger antennae compared to females.

2. **Analyzing the Options**:
- **(a) Anal styles**: These are structures found in male cockroaches that are used for copulation. They are not present in females.
- **(b) Anal cerci**: These are paired structures found in females and are used for sensory functions. They are a distinguishing feature of female cockroaches.
- **(c) Collateral glands**: These are present in both sexes and do not help in distinguishing between them.
- **(d) Ocelli**: These are simple eyes present in both male and female cockroaches and do not serve as distinguishing features.

3. **Conclusion**:
- The correct answer to the question is **(b) Anal cerci**, as they are specifically present in females and help in distinguishing them from males.

### Final Answer:
The structures which help in distinguishing a male cockroach from a female cockroach are **(b) Anal cerci**.