Single-blind procedure.
Single-blind trials occur when participants are consciously unaware of either the assigned group or important information about the material being evaluated, and the experimenter is aware of this knowledge. ..
Even in a double-blind experiment, participants do not know whether they belong to the experimental group or the control group. How to examine people with psychological help from a psychologist.
Listen to the pronunciation. (BLINE-did STUH-dee) A type of study in which the patient (single-blind) or the patient and her doctor (double-blind) do not know which drug or treatment is being administered. The opposite of an open-label trial is an open-label trial.
Learn more about single-blind at
brainly.com/question/3453118
#SPJ1
The answer is A because the others don't make sense.
