Taking a Broader Perspective: the Problem of External Validity Manufacturers

Multiple Choice

Taking a Broader Perspective: The Problem of External Validity Manufacturers often test new products like shampoo on laboratory animals and then generalize their results to humans because

A) human testing may be unethical due to the risk of injury.
B) it is easier to replicate animal studies than human studies.
C) it is often difficult to obtain human volunteers to test personal care products.
D) laboratory animals and humans often show identical allergic reactions.