Two Single Wave Pulses Are Sent Along a Rope

Multiple Choice

Two single wave pulses are sent along a rope. Both have the same height, but one is upward and the other is downward. As they are passing through each other, they will momentarily cancel each other out. What becomes of their energy as they are passing through each other?

A) It is still there in the form of gravitational energy of the rope.
B) Actually the pulses contained no energy to begin with.
C) It is momentarily destroyed due to destructive interference.
D) It is still there in the form of thermal energy of the rope and air.
E) It is still there in the form of kinetic energy of the rope.