<span>Control of physiological activities. Homeostasis involves the steady state and regulation of the body's internal environment. Irritability is the ability to respond to a stimulus.</span>
Answer:
The fourth plant that receives pure water is the control group.
Explanation:
The election of a control group is essential in an experiment. Its principal purpose is to allow the discrimination of the results obtained by the treatment in the study, in this case, <em>the different concentrations of salty water that each plant receives</em>. The control group provides a reference point. It must be selected from the same population of the treatment groups. Both groups must be similar in every variable that might influence the results, <u>except for the study treatment.</u>
The oxygen in the water molecule attracts the most electrons and in so doing attracts a slightly negative charge.