Jamie and Lynn were sure that they had answered most of the multiple-choice questions correctly because "the questions required only common sense." However,they each scored less than 60% on the exam.This best illustrates

A) a confounding variable.
B) random assignment.
C) hindsight bias.
D) overconfidence.

Overconfidence

The state of being excessively confident, to the point of having an unrealistic perception of one's abilities or outcomes.

Hindsight Bias

The tendency to believe, after an event has occurred, that one would have predicted or expected the outcome, also known as the "knew-it-all-along" effect.

Confounding Variable

An external factor in a research study that correlates with both the dependent and independent variables, potentially skewing results.