Final answer:
In a study exploring whether radiation causes illness, the independent variable is the 'Amount of radiation', the dependent variable is the 'Evidence of cancer control', and the control is likely 'People who are not exposed to radiation'. Control variables are essential in experiments to ensure a fair comparison and accurate findings.
Step-by-step explanation:
To answer the question 'Does exposure to radiation cause illness?', you will need to define and differentiate your variables.
The independent variable is the one that is changed or controlled in a scientific experiment to test the effects on the dependent variable. In this case, the independent variable would be 'b. Amount of radiation' since it is what is being manipulated to see if it has an effect on illness.
The dependent variable is the variable being tested and measured in a scientific experiment. For this question, the dependent variable is 'c. Evidence of cancer control,' as it is the outcome that may change in response to exposure to radiation.
The control is a standard or set of conditions that are kept constant and unchanging throughout an experiment. It is used for comparison. Here, the control would likely be 'a. People who are not exposed to radiation,' to compare against those who are exposed.
Control variables are important because they allow for a more accurate determination of the relationship between the independent and dependent variables. They help to isolate the relationship between the variables being examined and eliminate alternate explanations of the observed outcome.