Final answer:
False dichotomy occurs in an argument when a limited number of possibilities are assumed to be the only available options, ignoring the possibility of other alternatives. This fallacy artificially limits the available options and presents an either/or scenario without considering other options.
Step-by-step explanation:
False dichotomy, or "false dilemma," occurs in an argument when a limited number of possibilities are assumed to be the only available options. In the classic variation, the arguer offers two possibilities, shows that the one cannot be true, and then deduces that the other possibility must be true. This is a fallacy because it artificially limits the available options and ignores the possibility of other alternatives. For example, someone might argue that you either support the government completely or you are against it, ignoring the possibility of having mixed opinions or supporting some policies while opposing others.