Which of the following sentences describes the main idea of this passage?
A. Although many people think that wolves are the only animals who howl at the moon, dogs also seem to howl at the moon as well.
B. While it may appear as though wolves are howling at the moon, no one knows for sure if this is what they are actually doing.
C. Scientists disagree whether wolves really howl at the moon. Many have developed theories to support or deny that this is what wolves are actually doing.
D. Even though it looks like wolves are howling at the moon, they are really just communicating with each other.
E. Wolves howl at the moon for different reasons. Evidence suggests that this is mostly done to assist in communication.