To test a new drug that has the potential of curing people of the common cold, a company asked human volunteers who were coughing and sneezing to participate in a clinical study. the objective of the experiment was to test whether the new drug could cure the volunteers in the experimental group of the common cold. but instead of two groups, these volunteers were randomly divided into three groups and treated as follows: why was a second control group was included in this experiment?

To help researchers conclude that results are related to the new drug and not to the orange juice.

Explanation:

I could be wrong, Hope this helps

The correct answer will be- control group acts as a reference to the experimental groups.

Explanation:

A scientific experiment is divided into two groups of samples: the experimental and the control group.

In the experimental group, the variable to be tested is taken into account that is the key component is studied whereas in the control group the key variable is missing and the experiment is performed into the natural conditions.  

In the given conditions, the control group is formed to compare the results of the experimental group as a control group acts as a reference to the experimental group.

the answer is b. glad to .