In interphase, the primary event that occurs is:
A. cells replicate (duplicate) their chromosomes
Interphase is the phase of the cell cycle where the cell prepares for division. It consists of three subphases: G1 (gap 1), S (synthesis), and G2 (gap 2). During the S phase, DNA replication occurs, resulting in the duplication of chromosomes.
Option B (DNA coils up into chromosomes) typically occurs during the later phases of the cell cycle, specifically during prophase of mitosis, not in interphase.
Option C (the cell divides) refers to the process of mitosis or meiosis, which happens after interphase has been completed.