Immune system cells enter a resting phase after undergoing mitosis. When activated—for example, by an infection—they can reenter the sequence of events in the cell cycle that leads to cell division. What would be the correct cell cycle sequence of events for these reactivated cells?

Explanation:

The most Immune system cells enter a resting phase after undergoing mitosis. In resting stage, cell enter an inactive stage and do not divide. After activation by an infection  or other type of signal, they re-enter into the sequence of events in the cell cycle that leads to cell division.  

Correct cell cycle sequence of events for these reactivated cells from G0 to G1  and leads to cell division , G0 to  G1, S G2, mitosis, or M stage ( prophase, metaphase , anaphase and telophase) and cytokinesis.

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