Which statement makes a prediction for the hypothesis "bird species have decreased in number in a particular wetland due to construction traffic"?

A) If a wetland area is disturbed by construction vehicles, then the number of bird species will decrease.
B) If construction vehicles are in a wetland, then the birds will become too frightened to reproduce.
C) If bird numbers decrease in a wetland, then construction vehicles must have polluted the environment.
D) If construction vehicles enter a wetland, then new predators will arrive and reduce the bird populations.