Answer:
A. Independent variable
Explanation:
Independent variable is one that represents a variable that influences or affects another variable. Independent variables are the determining factor, condition, or cause for a given outcome, effect, or consequence. They are also the factor manipulated by the researcher in order to determine the factor's relationship with the observed phenomenon, to see what influence it has on a possible outcome. For this reason, we can say that the example of the independent variable that is presented in the question is price changes.