[A]: Dolly, a sheep is an example of cloning.
[R]: Cloning in another sense is sexual reproduction.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

**Step-by-Step Solution:**

1. **Understanding Cloning**: Cloning is defined as the process by which an individual produces an exact genetic copy of itself. The resulting copies are referred to as clones. This process is typically associated with asexual reproduction, where offspring are produced without the fusion of gametes.

2. **Dolly the Sheep**: Dolly was the first mammal to be cloned from an adult somatic cell. She was created using a technique called somatic cell nuclear transfer (SCNT). In this process, a mammary cell from a donor sheep (Finn Dorset) was fused with an egg cell from another sheep (Scottish Blackface) from which the nucleus had been removed.

3. **Process of Cloning Dolly**:
- The mammary cell from the Finn Dorset sheep served as the nuclear donor.
- The egg cell from the Scottish Blackface sheep acted as the cytoplasmic donor.
- An electric shock was applied to the fused cell to stimulate it to divide and develop into a blastocyst.
- This blastocyst was then implanted into a surrogate mother, leading to the birth of Dolly on July 5, 1996.

4. **Evaluating the Assertion and Reason**:
- The assertion states that "Dolly, a sheep, is an example of cloning." This statement is true, as Dolly was indeed cloned.
- The reason provided states that "cloning in another sense is sexual reproduction." This statement is false because cloning is primarily associated with asexual reproduction, not sexual reproduction.

5. **Conclusion**: Since the assertion is true and the reason is false, the correct answer is that the assertion is true, but the reason is false.

---