[A]: Proteins are polymers of amino acids.
[R]: Nucleic acids are polymers of units known as nucleotides

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

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Proteins are polymers of amino acids."
- Proteins are indeed macromolecules made up of long chains of amino acids linked together by peptide bonds. This statement is true.

2. **Understanding the Reason:**
- The reason states that "Nucleic acids are polymers of units known as nucleotides."
- Nucleic acids, such as DNA and RNA, are indeed composed of smaller units called nucleotides, which are linked together by phosphodiester bonds. This statement is also true.

3. **Analyzing the Relationship:**
- While both the assertion and reason are true, they describe different types of biological macromolecules (proteins and nucleic acids) and do not explain each other.
- Therefore, the reason is not a correct explanation of the assertion.

4. **Conclusion:**
- Since both the assertion and reason are true, but the reason does not explain the assertion, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

**Final Answer:**
- The correct option is (B): Both assertion and reason are true, but the reason is not the correct explanation.

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