A single set of chromosomes is found in
I. Germinal cell
II. spermatogonium
III. primary spermatocyte
IV. Secondary Spermatocyte
V. Spermatid

Options

A. ii, iii, iv and v
B. i, iii, iv and v
C. Only iv and v
D. Only v

Answer

To determine which of the given cells contains a single set of chromosomes, we need to analyze each option based on their chromosomal composition:

1. **Germinal Cell**: Germinal cells are diploid (2n), meaning they contain two sets of chromosomes. Therefore, this option does not have a single set of chromosomes.

2. **Spermatogonium**: Spermatogonia are also diploid (2n) cells. They are the primordial germ cells in males and contain two sets of chromosomes. Thus, this option does not have a single set of chromosomes.

3. **Primary Spermatocyte**: Primary spermatocytes are diploid (2n) as well. They undergo meiosis to form secondary spermatocytes. Therefore, this option does not have a single set of chromosomes.

4. **Secondary Spermatocyte**: Secondary spermatocytes are haploid (n), meaning they contain a single set of chromosomes. This option does have a single set of chromosomes.

5. **Spermatid**: Spermatids are also haploid (n) and are formed from secondary spermatocytes after the second meiotic division. This option also has a single set of chromosomes.

**Conclusion**: The cells that contain a single set of chromosomes are the **Secondary Spermatocyte (IV)** and **Spermatid (V)**.

### Final Answer:
The correct options that contain a single set of chromosomes are **IV (Secondary Spermatocyte) and V (Spermatid)**.

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