What question do the courts ask in deciding the standard of care to apply?

A) What would an average person in society have done?
B) Was it reasonable to foresee the damage that would occur if the act was done?
C) What would a reasonable person have done under similar circumstances?
D) What would an extremely cautious person have done under the circumstances?
E) What would I, the judge or jury, have done in the circumstances?

C