What is the single most important factor that defines desert biomes? why are deserts divided into different types?

Pls quickly! which of the following is true about the behavior of an organism? a. the behavior of an organism is influenced by both its heredity and it’s environment. b. the behavior of an organism is influenced only by the treats it inherits from its parents. c. the behavior of an organism is influenced only by the environment in which it lives in. d. the behavior of an organism is not influenced by either it’s heredity or its environment.