Metaphor is describing a trait to compare a physical attribute. "Pale as a ghost" describes a person with a white sickly appearance. descriptive way to describe a condition to make the listener "visualize" the meaning.
Metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another. It may provide clarity or identify hidden similarities between two ideas. Metaphors are often compared to other types of figurative language, such as antithesis, hyperbole, metonymy and simile.
C is the choice I would make because I believe the writer is planning to answer this question: "and how come we think dogs are so smart". The writer never tells us what dogs can't do (a) or mention others being dumb (b) and doesn't make fun of humans (d)
