In mitosis, chromosome duplication occurs during

Options

A. Interphase
B. Prophase
C. Late prophase
D. Late telophase

Answer

**Step-by-Step Solution:**

1. **Understanding Mitosis**: Mitosis is a type of cell division that results in two daughter cells, each with the same number of chromosomes as the parent cell. It is an equational division, meaning the chromosome number remains constant.

2. **Identifying Phases of the Cell Cycle**: The cell cycle consists of interphase and the mitotic phase (M phase). Interphase is further divided into three phases: G1 (Gap 1), S (Synthesis), and G2 (Gap 2).

3. **Focus on Interphase**: The question asks about chromosome duplication in mitosis. Chromosome duplication occurs during interphase, specifically in the S phase.

4. **Role of the S Phase**: During the S phase of interphase, DNA replication occurs. This means that each chromosome is duplicated, resulting in two sister chromatids for each chromosome.

5. **Conclusion**: Therefore, the correct answer to the question "In mitosis, chromosome duplication occurs during" is during the S phase of interphase.

**Final Answer**: Chromosome duplication occurs during the S phase of interphase.

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