You are conducting an experiment to test whether a new medication will people with hypertension to lower their blood pressure. which of the following would be your control? a.) how many people were tested b.) a group of test subjects who were given the new medication c.) the group of test subjects who took a placebo (a tablet without the medicine) d.) how much the medication costs

C.) the group of test subjects who took a placebo.  

Hello!

The control in an experiment is the part of an experiment which you are basing yours off of, for example, if an experiment was how much faster a flower would grow with a new fertilizer in the soil, the control would be the growth rate of the flowers without any fertilizer.

In this case, the thing being experimented with is the new medication. So the control would be the people without the medicine, or in this case, the placebo (as it essentially has the same effect.)

Therefore, your answer would be C.

Hope this helped!