Final answer:
Eric's explanation shows his external locus of control.
Step-by-step explanation:
Eric's explanation shows his external locus of control. Locus of control refers to our beliefs about the power we have over our lives. People with an external locus of control tend to believe that their outcomes are outside of their control, often attributing their successes or failures to luck or chance. Since Eric believes that he did well on his exams because they were easy and due to good luck, it indicates that he has an external locus of control.