Assertion. CO and NO both combine with hemoglobin
Reason. NO has more affinity than CO towards haemoglobin.

Options

A. If 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. If Assertion is true but Reason is false
D. If both Assertion and Reason are false

Explanation

To analyze the assertion and reason provided in the question, we can break it down step by step:

### Step 1: Understanding the Assertion
The assertion states that both carbon monoxide (CO) and nitric oxide (NO) combine with hemoglobin.

- **Explanation**: Hemoglobin is a protein in red blood cells that carries oxygen. Both CO and NO can bind to hemoglobin, but they do so in different ways and with different effects.

### Step 2: Understanding the Reason
The reason states that NO has more affinity than CO towards hemoglobin.

- **Explanation**: Affinity refers to the strength of the binding between a molecule and hemoglobin. While NO does bind to hemoglobin, it is important to note that CO actually has a much higher affinity for hemoglobin than NO. CO binds to hemoglobin over 200 times more tightly than oxygen, which can lead to serious health risks, including carbon monoxide poisoning.

### Step 3: Evaluating the Assertion and Reason
Now we need to evaluate the truth of both the assertion and the reason.

- **Assertion Evaluation**: The assertion is true; both CO and NO can combine with hemoglobin.
- **Reason Evaluation**: The reason is false; CO has a higher affinity for hemoglobin than NO.

### Step 4: Conclusion
Since the assertion is true but the reason is false, we can conclude that the statement as a whole is incorrect.

### Final Answer
The assertion is true, but the reason is false.

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