I assume that the context is story-telling and the high point refers to the high point of the story, or the one moment in which the decision is made that will influence the rest of the story: this is called climax (answer a).
The conflict might happen before the climax, and lead to it.
You can’t explain it scientifically.
Isabels hypothesis should be that if i leave my cat chicken flavored food then my cat would eat it
Really, it's C, because A and B are actually the opposite of what happened.
Heuristic; its a way of learning that enables a person to learn for themselves using a practical method that is not guaranteed to be perfect but is sufficient for immediate goals.