Final answer:
The statement (D) William's test anxiety helps him score higher on the exam exemplifies the Yerkes-Dodson law, which predicts that optimal levels of arousal can enhance performance depending on the task complexity.
Step-by-step explanation:
The Yerkes-Dodson law states that there is an optimal level of arousal for performance, which varies depending on the complexity of the task at hand. For simple tasks, higher levels of arousal typically lead to better performance, while for complex tasks, lower arousal levels are more conducive to good performance. The statement that best exemplifies the Yerkes-Dodson law is:
(D) William's test anxiety helps him score higher on the exam.
As William's anxiety (a form of arousal) increases to a moderate level, his performance on the exam also improves, which is in line with the Yerkes-Dodson law's prediction of optimal arousal leading to the best performance.
The Yerkes-Dodson law states that the optimal arousal level for performance depends on the complexity of the task. For simple tasks, high arousal is best, while for complex tasks, lower arousal is better. An example of this is Linda spending hours playing a challenging video game because the activity arouses and motivates her (option C).