A cornered king…

… with the opponent already controlling one long diagonal and about to occupy the second usually means red alert. Here White has played 30.Qe5 holding a pistol to Black’s head. What do you think about that?

A) A real knockout blow, forcing immediate resignation;
B) Not bad, but a surprising trick lets Black escape into an endgame;
C) The move is rubbish, throwing away White’s entire advantage.
The solution is here,
but first ponder it with a larger version of the diagram.