Assertion: In eukaryotic chromosome, DNA is long, double-stranded and linear.
Reason: The eukaryotic chromosomes are composed of DNA, proteins, RNA, metal ions and enzymes.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. If Assertion is true but the Reason is false.
D. If both Assertion and Reason are false.

Answer

### Step-by-Step Text Solution:

1. **Understanding the Assertion**:
- The assertion states that in eukaryotic chromosomes, DNA is long, double-stranded, and linear.
- This is true because eukaryotic DNA is organized into long strands that are double-stranded and have a linear structure, as opposed to prokaryotic DNA, which is typically circular.

2. **Understanding the Reason**:
- The reason given states that eukaryotic chromosomes are composed of DNA, proteins, RNA, metal ions, and enzymes.
- This statement is also true. Eukaryotic chromosomes consist of DNA wrapped around histone proteins, and they may also contain RNA, various metal ions, and enzymes that assist in DNA replication and repair.

3. **Analyzing the Relationship**:
- While both the assertion and the reason are correct, the reason does not explain why the DNA in eukaryotic chromosomes is long, double-stranded, and linear.
- The reason provides information about the composition of chromosomes but does not clarify the structural characteristics of the DNA itself.

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

### Final Answer:
- The correct option is 2: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.