Which of the Following Is True with Regard to Using

Which of the following is true with regard to using animals as research subjects?

A) Many of the basic biological mechanisms underlying animal behaviors are significantly different than those underlying human behaviors.
B) Animal protection organizations have suggested that the only way to ethically study animals is to observer them in their natural environments rather than in laboratory settings.
C) It is possible to obtain informed consent when using animal subjects.
D) Animal suffering is a variable that does not need to be considered when designing an experiment because animals' brains are not capable of registering pain or discomfort in a way that interferes with legitimate research questions.