The terms 'clone' cannot be applied to offspring formed by sexual reproduction because

Options

A. offspring do not possess exact copies of parental DNA
B. DNA of only one parent is copied and passed on to the offspring
C. offspring are formed at different times
D. DNA of parent and offspring are completely different

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Clones:**
- Clones are organisms that are genetically identical to each other and to their parent. This occurs in asexual reproduction, where only one parent contributes genetic material.

2. **Asexual Reproduction:**
- In asexual reproduction, a single parent produces offspring without the involvement of gametes (sperm and egg). The offspring are exact copies of the parent, leading to no genetic variation.

3. **Genetic Contribution in Asexual Reproduction:**
- Since only one parent's genetic material is involved, all offspring are genetically identical. This lack of genetic variation is what defines them as clones.

4. **Sexual Reproduction:**
- In contrast, sexual reproduction involves two parents. Each parent contributes genetic material, resulting in offspring that have a combination of genes from both parents.

5. **Genetic Variation in Sexual Reproduction:**
- The mixing of genetic material from two different parents leads to genetic variation among the offspring. While they may share similarities with their parents, they are not identical.

6. **Conclusion:**
- Therefore, the term 'clone' cannot be applied to offspring formed by sexual reproduction because they do not contain an exact copy of parental DNA. Instead, they exhibit genetic diversity due to the contribution of two different parental genetic materials.

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