The Yerkes-Dodson law says:
a) A simple task is performed best when arousal levels are relatively high and complex tasks are best performed with arousal levels are lower.
b) Arousal levels do not influence performance of complex tasks, but do for simple tasks.
c) Arousal levels do not influence performance of simple tasks, but do for complex tasks.
d) A simple task is performed best when arousal levels are lower, and complex tasks are best performed with arousal levels are relatively high.