[A]: Smoking stimulates secretion of gastric juice in stomach even when stomach is empty.
[R]: It is aimed at quickening the digestion of food when taken

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

To analyze the assertion and reason provided in the question, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Smoking stimulates secretion of gastric juice in the stomach even when the stomach is empty."
- This is a true statement. Smoking has been shown to increase gastric acid secretion, which can lead to various gastrointestinal issues, including ulcers.

2. **Understanding the Reason (R)**:
- The reason states that "It is aimed at quickening the digestion of food when taken."
- This statement is misleading. While smoking does stimulate gastric juice secretion, it does not serve the purpose of aiding digestion effectively. In fact, smoking can lead to negative health effects, including the development of ulcers, which can hinder digestion rather than aid it.

3. **Evaluating the Relationship Between A and R**:
- We need to determine if the reason provided accurately explains the assertion.
- Since the assertion is true but the reason is false, we conclude that the reason does not provide a correct explanation for the assertion.

4. **Conclusion**:
- Based on the analysis, we can categorize the truth values:
- Assertion (A) is true.
- Reason (R) is false.
- Therefore, the correct answer is that A is true and R is false.

### Final Answer:
- The correct option is: **A is true and R is false.**

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