Loops of lampbrush chromosome are composed of
(a) Protein and RNA
(b) Double helix DNA only
(c) Double helix DNA , protein and RNA
(d) Single stranded DNA, protein and RNA

Options

A. Protein and RNA
B. Double helix DNA only
C. Double helix DNA , protein and RNA
D. Single stranded DNA, protein and RNA

Explanation

To solve the question about the composition of loops in lampbrush chromosomes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Lampbrush Chromosomes**:
- Lampbrush chromosomes are a type of giant chromosome found in the growing oocytes of vertebrates, particularly during the diplotene stage of meiosis.

2. **Identifying the Structure**:
- These chromosomes consist of loops that extend from the chromomeres (the bead-like structures along the chromosome).

3. **Composition of the Loops**:
- The loops of lampbrush chromosomes are primarily made up of double-stranded DNA. This is crucial to note as it distinguishes them from other types of genetic material.

4. **Excluding Other Options**:
- While the loops may interact with proteins and RNA, the primary structural component of the loops is double-stranded DNA. Therefore, options that suggest the loops are made up of only proteins or RNA, or a combination that does not include double-stranded DNA as the main component, can be ruled out.

5. **Conclusion**:
- Based on the information, the correct answer is (b) Double helix DNA only, as it accurately reflects the primary composition of the loops in lampbrush chromosomes.

### Final Answer:
(b) Double helix DNA only