Why Have Most States Replaced the Contributory Negligence Defense with a Comparative

Why have most states replaced the contributory negligence defense with a comparative negligence theory?

A) In order to assist a defendant in defending against unfounded claims.
B) In order to assist a plaintiff in avoiding the assumption of the risk doctrine.
C) In order to assist a defendant in avoiding the assumption of the risk doctrine.
D) Because of situations in which a plaintiff is barred from recovery due to minimal contributory negligence.
E) Because of situations in which a defendant is released from liability based on the last clear chance doctrine when equity requires that the defendant bear at least some responsibility.