When two parent of opposite sex participate in the reproductive process involving fusion of male and female gametes, it is called.

Options

A. Asexual reproduction
B. Sexual reproduction
C. Vegetative reproduction
D. Parasexual reproduction

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the type of reproduction that involves two parents of opposite sexes participating in the reproductive process, specifically focusing on the fusion of male and female gametes.

2. **Analyzing the Options**:
- **Option A: Asexual Reproduction**: This type of reproduction involves only one organism and does not require the fusion of gametes from two parents. Therefore, this option is incorrect.
- **Option B: Sexual Reproduction**: This is the process where two parents of opposite sexes (male and female) contribute gametes (sperm and egg) that fuse to form a zygote. This option fits the description provided in the question.
- **Option C: Vegetative Reproduction**: This method involves new plants being formed from vegetative parts (like stems, roots, or leaves) and does not involve gametes or two parents. Hence, this option is also incorrect.
- **Option D: Parasexual Reproduction**: This is a non-sexual mode of reproduction involving genetic recombination without meiosis and does not result in the formation of a zygote. Thus, this option is incorrect as well.

3. **Conclusion**: After analyzing all the options, the correct answer to the question is **Sexual Reproduction**. This is characterized by the involvement of two parents of opposite sexes and the fusion of their gametes.

**Final Answer**: Sexual Reproduction

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