You observe two different prey species reduce their total activity level after they smell the urine scent of the same predator. Which of the following can you conclude about this observation?

A) The urine contains a pheromone.
B) The urine is a general odorant.
C) The observation is an example of a bystander effect.
D) This is an example of odor mimicry.
E) This is an example of a communication network.