Which one of the following shows crossing over and variations

Options

A. Vegetative reproduction
B. Parthenogensis
C. Sexual reproduction
D. apomixis

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which process shows crossing over and variations. We need to identify a reproductive process that involves these two aspects.

2. **Identifying Key Terms**:
- **Crossing Over**: This is a process that occurs during meiosis, specifically in prophase I, where homologous chromosomes exchange genetic material.
- **Variations**: This refers to genetic diversity that arises from processes like crossing over during gamete formation.

3. **Linking to Reproductive Processes**:
- **Meiosis**: This is the type of cell division that produces gametes (sperm and eggs) and is associated with sexual reproduction. It includes crossing over and leads to genetic variation.
- **Sexual Reproduction**: Involves the formation of gametes through meiosis, thus leading to crossing over and variations.

4. **Evaluating Options**:
- **Option 1: Vegetative Reproduction**: This is a form of asexual reproduction that does not involve gametes or meiosis, hence no crossing over or variations.
- **Option 2: Parthenogenesis**: This is the development of an organism from an unfertilized egg, which also does not involve gametes or crossing over, leading to no variations.
- **Option 3: Sexual Reproduction**: This involves meiosis, which includes crossing over and results in genetic variations.
- **Option 4: Apomixis**: This is the formation of seeds without fertilization, again lacking gametes and crossing over, resulting in no variations.

5. **Conclusion**: Based on the analysis, the only option that involves crossing over and variations is **Option 3: Sexual Reproduction**.

---