Assertion. DNA is more stable while RNA is more reactive.
Reason. DNA was first discovered by Watson and Crick (1953).

Options

A. Both Assertion and Reason are true and Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion
C. Assertion is true but Reason is false
D. Both Assertion and Reason are false

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "DNA is more stable while RNA is more reactive."
- To evaluate this, we need to consider the structural differences between DNA and RNA.

2. **Analyzing the Structure of DNA and RNA:**
- DNA (deoxyribonucleic acid) contains deoxyribose sugar, while RNA (ribonucleic acid) contains ribose sugar.
- The key difference is that ribose has a hydroxyl group (-OH) at the 2' carbon, whereas deoxyribose has only a hydrogen atom (-H) at the 2' carbon.

3. **Stability of DNA vs. Reactivity of RNA:**
- The presence of the hydroxyl group in RNA makes it more susceptible to hydrolysis and nucleophilic attacks, which leads to its increased reactivity.
- Conversely, the absence of the hydroxyl group in DNA contributes to its stability, making it less reactive and more suitable for long-term genetic information storage.

4. **Conclusion on the Assertion:**
- Therefore, the assertion that "DNA is more stable while RNA is more reactive" is **true**.

5. **Understanding the Reason:**
- The reason states that "DNA was first discovered by Watson and Crick (1953)."
- However, this is incorrect. DNA was first identified by Friedrich Miescher in 1869, who called it "nuclein." Watson and Crick are credited with elucidating the double-helix structure of DNA in 1953, but they did not discover DNA itself.

6. **Conclusion on the Reason:**
- Thus, the reason provided is **false**.

7. **Final Evaluation:**
- The assertion is true, but the reason is false. Therefore, the correct answer is that the assertion is true, and the reason is false.