Similarity in Ascaris lumbricoides and Anopheles stephensi is

Options

A. Sexual dimorphism
B. Metamerism
C. Anaerobic respiration
D. endoparasitism

Answer

### Step-by-Step Solution:

1. **Identify the Organisms**:
- Ascaris lumbricoides is a parasitic roundworm belonging to the phylum Nematoda.
- Anopheles stephensi is a species of mosquito belonging to the phylum Arthropoda.

2. **Understand the Concept of Sexual Dimorphism**:
- Sexual dimorphism refers to the differences in appearance between male and female members of the same species. This can include differences in size, color, shape, and other physical characteristics.

3. **Analyze the Similarity**:
- Both Ascaris lumbricoides and Anopheles stephensi exhibit sexual dimorphism. This means that the males and females of both species can be distinguished from each other based on their morphological characteristics.

4. **Conclusion**:
- The similarity between Ascaris lumbricoides and Anopheles stephensi is that both show sexual dimorphism.

5. **Select the Correct Answer**:
- Based on the analysis, the correct answer is option A: Sexual dimorphism.