Suppose a Biologist Has Data Showing Both the Divergence Times

Multiple Choice

Suppose a biologist has data showing both the divergence times between species and the number of changes at a gene for the species.Now suppose that the biologist plots divergence time on the x axis and the number of changes on the y axis.If a molecular clock is operating, then the slope of that curve must be

A) increasing.
B) constant.
C) decreasing.
D) one change per million years.
E) zero.