Which statement describes the mapping? Group of answer choices

A. The mapping does not represent y as a function of x, because two of the x-values corresponds to the same y-value.

B. The mapping represents y as a function of x, because each y-value corresponds to exactly one x-value.

C. The mapping does not represent y as a function of x, because there are more x-values than different corresponding y-values.

D. The mapping represents y as a function of x, because each x-value corresponds to exactly one y-value.