Which of the following is NOT a category of cells with respect to the cell cycle?

The classification of cells according to their behavior in the cell cycle includes those that never divide after a certain point, those that constantly divide (like stem cells and certain epithelial cells), and those that can be stimulated to divide under specific conditions or signaling (such as certain immune cells).

Cells do enter a phase called M phase, during which division occurs, but all cells that undergo the cell cycle participate in various stages, including interphase (G1, S, and G2) prior to reaching M phase. M phase alone does not encompass the full range of cell activity or the entirety of the cell cycle. Therefore, it is misleading to categorize cells as simply those that “divide only during M phase,” because this ignores the crucial preparatory phases that occur before division and does not accurately reflect the behavior of cells in the cell cycle. This is why this choice is not considered a valid category.