Answer:
The answer is A) double-blind experiment
Step-by-step explanation:
Blinded studies are a useful way to avoid bias in the results of a study. In a randomized double-blind study, the subjects, in this case the mice, are randomly assigned to a group of treatment. Double-blind refers to the fact that neither the researcher nor the subjects of study know which group is receiving a specific treatment. Single-blind is a study in which the physician or researcher is aware of the treatment that is being given but the subjects of study are not. Clinical trials are done in human patients, not in animals, those are called preclinical trials. The common terms for blinded studies are: unblinded, single-blinded, double-blinded and triple-blinded not fully-blinded.