The Diagram Shows the Sequence of Events That Occur as Sound

The diagram shows the sequence of events that occur as sound waves are converted into electrical impulses. Which of the following statements best describes what is occurring at the point marked 4 in the diagram?

A) Movement of the stapes in the oval window creates waves in the perilymph.
B) Movement of the stapes in the round window creates waves in the perilymph.
C) Movement of the incus in the oval window creates waves in the perilymph.
D) Movement of the incus in the round window creates waves in the perilymph.
E) Movement of the tympanic membranes moves the malleus.