A causal study is one that _____.

a. Attempts to capture a population's characteristics by making inferences from a sample's characteristics and testing resulting hypotheses
b. Emphasizes a full contextual analysis of a few events or conditions and their interrelations
c. Discovers answers to the questions who, what, when, where, or how much
d. Attempts to reveal why or how one variable produces changes in another Provides repeated measures over an extended period of time

Explanation: Causal research is the study of cause-and-effect interactions, also called causal analysis. It is necessary to examine the variance in the supposed factor to cause the shift in the other variable(s) in order to determine causal link, and then calculate the changes in the other variable(s).

It is necessary to control other conflicting variables so that they do not affect the findings, by either keeping them constantly in the observational production of information or by using statistical techniques.