Answer the following question: Fact 1: Male dogs use pheromones in urine to mark their territory. Fact 2: Pheromones are a sub-category of semiochemicals. Given the two facts above, what do dogs use to mark their territory?

OPT:
A). water
B). Chemicals
C). layers of fat
D). food
E). Animal fur
F). heat energy
G). Scratches
H). heat produced
Answer:
B).