In Which of the Following Situations Would You Most Likely

In which of the following situations would you most likely experience the "fight or flight" syndrome?

A) You come around the corner in an unfamiliar house,see a glimpse of a person and you're startled.It's you in the mirror.
B) You are driving down the highway going about 10 miles over the speed limit and you see a police car out of the corner of your eye.
C) You are walking down a dark alley and you hear a noise.A man is coming toward you with a knife in his hand.
D) You are walking your dog down the sidewalk when suddenly he's out of his collar and running across the busy street.