To "prohibit" an action means to:

To "prohibit" an action means to forbid it. This term is often used in legal, formal, or authoritative contexts where specific actions are not permitted. By definition, when something is prohibited, it is not allowed or is restricted by rules or laws. The use of "prohibit" typically conveys a strong sense of restriction or control over a certain action, making it clear that engaging in that action is not permissible.

In contrast, the other options suggest a positive endorsement or allowance of an action, which directly opposes the meaning of "prohibit." Therefore, choosing "forbid it" captures the essence of the term accurately, while the other responses do not align with this concept.