To provide a baseline against which they can evaluate the effects of a specific treatment, experimenters make use of a(n)
a.
dependent variable.
b.
random sample.
c.
independent variable.
d.
control condition.
e.
experimental condition.

d.  control condition

Explanation:

When carrying out an experiment, a control condition is set up to provide a baseline against which the result of the experiment can be compared. For example, when measuring the effects of a new medication, a control group is usually set up and the members of the group are given a placebo. This will not contain any of the active ingredients of the medicine and it acts as a way to evaluate the real effects of the medication.

the consumer demand because the members have to be aware if people are going to buy what they want to sell in this case either energy drinks or a car wash.