The cell cycle comprises several stages through which a cell passes during its life, from its formation to its division into two daughter cells.

Option A : M (Mitotic phase) - This is the phase where the cell divides.

Option B : G₂ (Gap 2) - This is the phase of the cell cycle following DNA replication (S phase) and preceding mitosis (M phase). During this time, the cell will continue to grow and produce proteins necessary for cell division.

Option C : G₁ (Gap 1) - This phase follows cell division (M phase) and precedes DNA replication (S phase). In this phase, the cell grows and monitors its environment to determine whether it should initiate DNA synthesis.

Option D : G₀ (Gap 0) - This is a stage where cells are neither dividing nor preparing to divide. Instead, they are performing their designated functions and are in a state of dormancy or quiescence.

So, the quiescent stage of the cell cycle is :

Option D : G₀.