Cell fusion experiments involving the cell cycle

Which of the following is true of cell fusion experiments involving the cell cycle:

• • S-phase fusions can induce cells in G1 and G2 to enter S phase
  • S-phase fusions can induce cells in G2 to enter S phase
  • S-phase fusions can induce cells in G1 or M to enter S phase
  • M-phase fusions can induce G1 cells to enter M phase