A researcher conducts a study examining the alcohol consumption of college students. She brings the first group of students into the laboratory the week before spring break. She brings the second group of students into the laboratory the week after spring break. The difference in timing of the two groups may be a(n):

A. manipulated variable.
B. confounding variable.
C. independent variable.
D. dependent variable.

The correct answer is B. confounding variable

Explanation:

A researcher conducts a study examining the alcohol consumption of college students. She brings the first group of students into the laboratory the week before spring break. She brings the second group of students into the laboratory the week after spring break. The difference in timing of the two groups may be a CONFOUNDING VARIABLE

A confounding variable is an outside influence that changes the effect of a dependent and independent variable. This extraneous influence is used to influence the outcome of an experimental design. Simply, a CONFOUNDING VARIABLE is an extra variable entered into the equation that was not accounted for.

B. confounding variable.

Explanation:

A researcher conducts a study examining the alcohol consumption of college students. She brings the first group of students into the laboratory the week before spring break. She brings the second group of students into the laboratory the week after spring break. The difference in timing of the two groups may be a confounding variable:

A confounding variable is a variable that has the ability to influence both the independent and dependent variable. In this scenario, the different timing of   accessing the subjects could influence the independent and dependent variables and hence, is a confounder.