Final answer:
A mand is a B) linguistic concept that describes a type of verbal behavior used to express needs or desires through communication. It's a functional unit of language, essential in expressing requests or demands to influence one's surrounding environment.
Step-by-step explanation:
A mand in the context of verbal behavior is a linguistic concept that refers to a type of verbal behavior which is a request or demand. It is a functional unit of language used to express needs or desires and to influence the environment by communicating with others.
For instance, when a person says, "Can you pass the salt?" they are using a mand to request action from another. Mands are an important aspect of language development and can be taught and reinforced through various educational strategies.