Assertion (A): Dolly was the first cloned mammal. Reason (R): Dolly was produced by in vitro fertilization.

1. Assertion (A): States that Dolly the sheep was the first cloned mammal. Dolly, born in 1996, was the first mammal to be cloned from an adult somatic cell using the process of nuclear transfer. Assertion (A) is true. 2. Reason (R): States that Dolly was produced by in vitro fertilization (IVF). This is incorrect. IVF involves fertilizing an egg with sperm outside the body. Dolly was created using Somatic Cell Nuclear Transfer (SCNT), where the nucleus from an adult somatic cell was transferred into an enucleated egg cell, which was then stimulated to develop into an embryo. Reason (R) is false. 3. Conclusion: Since Assertion (A) is true and Reason (R) is false, the correct option is (C).