Question

What happens during destructive interference?
the crests and troughs of out-of-phase waves cancel each other out
the crests and troughs of two waves combine into one larger waveform
two waves add their effects to each other
waves move in opposite directions and repel each other

Answer 1

Figure A is destructive interference: the two waves have opposite displacements at the
instant they pass one another, and they add to zero.

Answer 2

So for your answer, I would say it is the first option: they waves are out-of-phase and they cancel each other out.