Two Games That Differ Only in the Timing of Moves-One

Multiple Choice

Two games that differ only in the timing of moves-one simultaneous,the other sequential move-can sometimes have completely different subgame-perfect equilibria. Why?

A) The second mover to choose non-credible threats.
B) The first mover can choose an action that it would deviate from if its action were secret.
C) Subgame-perfect equilibrium cannot be applied to simultaneous games.
D) All of the above.