Aclinical experiment is designed in such a way that neither the researchers dispensing a treatment nor the persons in the experimental or control groups know if they’re getting a sugar pill or a new drug this sort of experimental design is employing a/an procedure. a. experimenter expectations b. placebo c. double-blind d. reverse psychology

B.Placebo

Explanation:

A placebo is a medicine or treatment that is used for the psychological effect on the person rather than the physical. It has no effect but is used to test new drugs.

C.Double-blind

Explanation:

     The double-blind study methodology is probably the most important scientific invention since the scientific method. The purpose of the double-blind test is to avoid any conscious or unintentional interference with the results of an experiment. This requires the experiment to include a control group that nothing is done about (for example, if a drug is being tested for this group, a placebo is given), but that the group members do not know what they are receiving. This constitutes a simple blind test.

   To make the study even more free of subconscious tendencies, even the experimenter must not know what the expected result of the measurement is doing, which is called double-blind.

   Double-blind study or double-blind clinical trial is a human clinical trial method where neither the examiner nor the experimental groups knows what is being used as a variable at any given time.

the answer is barium and copper bromide