Which of the following has been adopted by courts to aid plaintiffs in establishing negligence claims?

A) Res ipsa loquitur only.
B) Negligence per se only.
C) Assumption of the risk only.
D) Res ipsa loquitur and negligence per se.
E) Res ipsa loquitur,negligence per se,and assumption of the risk.

The plaintiff has the burden of proving all four elements of a negligence case.Direct evidence of negligence by the defendant,however,is not always available.For example,there may have been no witnesses to the negligent conduct,and other evidence may have been destroyed.Therefore,two doctrines have been adopted by courts to aid plaintiffs in establishing negligence claims: res ipsa loquitur and negligence per se.