Assertion `:` Anti histammin does not effect secration of acid in stomach `:`
Reason `:` Anti Histamine and antacids work on different receptors.

Options

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

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states that "Antihistamine does not affect secretion of acid in the stomach."

- **Explanation**: Antihistamines are primarily used to treat allergic reactions by blocking histamine receptors (H1 receptors). They do not have a direct effect on the gastric acid secretion, which is mainly regulated by histamine acting on H2 receptors in the stomach.

### Step 2: Understand the Reason
The reason states that "Antihistamine and antacids work on different receptors."

- **Explanation**: Antihistamines target H1 receptors, while antacids do not act on histamine receptors at all. Instead, antacids neutralize stomach acid and are used to relieve symptoms of heartburn and indigestion. This indicates that they operate through different mechanisms and receptors.

### Step 3: Evaluate the Truth of Assertion and Reason
- **Assertion**: True. Antihistamines do not affect acid secretion in the stomach.
- **Reason**: True. Antihistamines and antacids work on different receptors.

### Step 4: Determine the Relationship Between Assertion and Reason
Since both the assertion and the reason are true, and the reason provides a correct explanation for the assertion, we can conclude that:

- **Conclusion**: Both assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
The correct option is: **Option A** - Both assertion and reason are true and reason is the correct explanation of assertion.

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