Answer:
M phase
Step-by-step explanation:
While there are many checkpoints within the cell cycle, the specific checkpoint you are referring to most likely takes place in the M (mitosis) phase.
Before the M phase (which includes the G1, S, and G2 phases), the cell grows, the number of organelles increases, and DNA replicates. After the G2 phase, the M phase begins. At the beginning of this phase, the DNA condenses, lines up in the center of the cell, attaches to spindle fibers, and is pulled to opposite ends of the cell. If this checkpoint receives the proper signal, the actual division of the cell will occur.