When a researcher directly controls or manipulates changes in an independent variable by exposing participants to the treatment conditions,
A) she is conducting a correlational study.
B) cause-and-effect relationships can be detected.
C) the correlational coefficient should be zero.
D) she is using a technique called matching.

Question

Quizplus · Accepted Answer

When a researcher directly controls or manipulates changes in an independent variable by exposing participants to the treatment conditions, cause-and-effect relationships can be detected. This is because the researcher can manipulate the independent variable to observe changes in the dependent variable, which cannot be done in a correlational study. Therefore, option B is the correct answer. Option A is incorrect because correlational studies do not involve manipulating independent variables. Option C is incorrect because the correlational coefficient is a statistical measure of the strength of the relationship between two variables and is not applicable in this context. Option D is incorrect because matching is a technique used to control extraneous variables in an experiment but does not directly manipulate the independent variable.

When a Researcher Directly Controls or Manipulates Changes in an Independent