Question

Cells that are not dividing are likely to be at

Answer 1

In a cell cycle, when a cell is in G1 or First Growth phase, a cell has three options.
1) To continue cell cycle and enter S-phase
2) To stop cell cycle and enter G0 phase for undergoing differentiation.
3) Hey arrested in G1 phase when it may enter G0 phase or re-enter cell cycle.

According to your question, when the cell doesn't divide, it should be at G0 phase.

Thanks.

Answer 2

Cells which are not dividing are likely to be at
(a) G
(b) G2
(C) G0
(d) S phase