Assertion. Carbon monoxide is highly toxic.
Reason. Carbon monoxide forms a stable complex with hemoglobin present in red blood cells.

Options

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

Answer

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

### Step 1: Understanding the Assertion
The assertion states that "Carbon monoxide is highly toxic." This is a true statement. Carbon monoxide (CO) is indeed considered highly toxic to humans and animals.

**Hint:** Remember that toxicity refers to the degree to which a substance can harm living organisms.

### Step 2: Understanding the Reason
The reason states that "Carbon monoxide forms a stable complex with hemoglobin present in red blood cells." This is also true. Carbon monoxide binds with hemoglobin in a manner that is much stronger than the binding of oxygen to hemoglobin.

**Hint:** Consider how hemoglobin's primary function is to transport oxygen, and how CO's binding interferes with this function.

### Step 3: Linking the Assertion and Reason
The assertion and reason are linked because the formation of a stable complex between carbon monoxide and hemoglobin directly leads to the toxicity of carbon monoxide. When CO binds to hemoglobin, it prevents oxygen from binding and being transported to vital organs, which can lead to suffocation and other serious health issues.

**Hint:** Think about the implications of one molecule competing with another for binding sites on hemoglobin.

### Step 4: Conclusion
Since both the assertion and the reason are true, and the reason explains the assertion, we can conclude that the assertion is correct and the reason is valid.

**Hint:** Evaluate whether the reason provides a logical explanation for the assertion.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains why carbon monoxide is highly toxic.

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