For Her Experimental Psychology Class, Kristen Has Developed the Hypothesis

For her experimental psychology class, Kristen has developed the hypothesis that intelligent people are more stressed out. Kristen's teacher tells her she needs to use operational definitions for her variables. This means that she needs to

A) define which behaviours or qualities differentiate one person's intelligence from the next person's, and define the behaviours she associates with stressed out.
B) explain what procedures she will use to collect her data.
C) define which variables are independent and which are dependent.
D) use self-report measures as part of her experiment.