Scientists include controls in their experiments why is a control important

"The control experiments are basically done to compare the main experiment and the experiment done in controlled manner so as to observe the changes and also to minimize the changing effect"

Explanation:

The scientists include the control in their experiments which can help them to minimize the changes and can observe the changes meticulously.  In control experiment the observation are made with minimum effect of the variables leaving the independent variable. This type of experiments help in increasing the reliability of the output. The control experiments are basically done to compare the main experiment and the experiment done in controlled manner so as to observe the changes.