Answer:B.Was exposed to the new teaching technique.
Explanation:An experimental group is a group in an experiment that receives the variable being tested.
Only one variable can be tested at the same time.
In an experimental research,there are two groups.One group receives the variable being tested and the other group do not receive the variable.
The group that do not receive the variable being tested is called the control group while the ones that receive it is called the experimental group.Results from these two groups are compared to conclude the experimental process.