Answer:
G₀ phase would be the correct answer.
G₀ phase also called resting phase is the phase in which a cell enters a quiescent state. In this state, the cell neither divides nor it prepares for cell division.
However, the cell remains metabolically active and performs all the vital functions.
Usually, mature or differentiated cells such as heart muscle cell, nerve cell et cetera exit the cell cycle and enter into this stage.
