Assertion : Palmitic acid has 20 carbon atoms including carboxy| carbon.
Reason : Arachidonic acid has 16 carbon atoms including carboxy| carbon.

Options

A. (A) Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
B. (B) Both the Assertion and the Reason are correct and the Reason is the incorrect explanation of the Assertion.
C. (C) Assertion is true but the Reason is false.
D. (D) both assertion and reason are false.

Explanation

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Palmitic acid has 20 carbon atoms including the carboxyl carbon."
- To evaluate this, we need to know the structure of palmitic acid. Palmitic acid is a saturated fatty acid with the chemical formula C16H32O2. It contains 16 carbon atoms in total, including the carboxyl carbon.
- Therefore, the assertion is **false**.

2. **Understanding the Reason**:
- The reason states that "Arachidonic acid has 16 carbon atoms including the carboxyl carbon."
- Arachidonic acid is a polyunsaturated fatty acid with the chemical formula C20H32O2. It actually contains 20 carbon atoms in total, including the carboxyl carbon.
- Therefore, the reason is also **false**.

3. **Conclusion**:
- Since both the assertion and the reason are false, the correct answer is that both the assertion and reason are false.

### Final Answer:
- The correct option is D: Both assertion and reason are false.

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