What occurs during cytokinesis?

During cytokinesis, the key process that occurs is the division of the cytoplasm of a parental cell, resulting in two distinct daughter cells. This phase follows mitosis, where the nucleus divides, but it specifically refers to the physical separation of the cytoplasmic contents. As a result of cytokinesis, each daughter cell is able to inherit the necessary organelles and cytoplasmic components to function independently. This is a crucial step in the cell cycle that ensures that each new cell maintains a full set of cellular machinery and resources.

The other processes mentioned in the other choices refer to different cellular events. The division of the nucleus into two nuclei happens during mitosis, not cytokinesis. Chromosome replication occurs during the S phase of the cell cycle, prior to mitosis and cytokinesis. Lastly, the transcription of DNA to RNA is a part of gene expression, which occurs both before and after cell division, but is not a part of the process of cytokinesis itself. Understanding these distinctions clarifies why the division of the cytoplasm is the defining feature of cytokinesis.