Answer:
multiple variables
Explanation:
Multiple variables entails that there may be more than one dependent variable and/or independent variable.
Such always comes to play out if you are conducting an experiment with multiple stages or sets of procedures.
In such type of experiments, there may be more than one set of measurements with different variables.
C it the right answer for this question hope it helps you
Answer:
The answer is B( the ability and willingness to buy a product