Which one of the following situations represents an internal conflict

You didn't list any situations, however, I can assist you in topics that would fit into the category.

Internal conflict is man vs self, or, man vs mind. It's when a person is conflicted with themselves, for example, questioning their next decisions, struggling to make a choice on their own because of mentality, etc.

So, internal conflict is like a conflict between a person and themselves - self-doubt, questioning an action, etc.

Hope this helps!