Professor Lyon decided to study food preferences of U.S. college students, so he asked his students to volunteer to participate in a lengthy survey. Professor Lyon's survey results are probably invalid because he did not use:
A) an operational definition.
B) random selection.
C) a valid hypothesis.
D) independent and dependent variables.

Question

Quizplus · Accepted Answer

Without random selection, the sample of students who volunteered may not accurately represent the entire population of U.S. college students, leading to a biased and potentially invalid survey result. The other options may also contribute to the validity of the study, but random selection is the most critical aspect for ensuring representativeness.

Professor Lyon Decided to Study Food Preferences of U