Answer:
The correct answer is option B. pheromones.
Explanation:
Pheromones are chemical substances that are released and produced by a different type of animals, into the environment, for marking their territory or affecting behaving of its species.
Wolves communicate by the chemical messages using their sense of smell. Such chemical messages are called pheromones, between different members of the same species.
Thus, the correct answer is option B. pheromones.