Final answer:
Low performance according to expectancy theory occurs when individual performance cannot be evaluated and when the task is easy, leading to social loafing and insufficient arousal levels.
Step-by-step explanation:
According to expectancy theory, conditions that result in low performance include situations where individual performance cannot be effectively evaluated or when a task is considered easy. When individual effort is not distinguishable within a group, a phenomenon known as social loafing may occur, leading to a decline in performance on simple tasks due to reduced motivation. Additionally, if the task is too easy, individuals may not feel sufficiently challenged, leading to lower levels of arousal and reduced performance. In contrast, informational social influence and optimal arousal levels suggest that performance can improve when individuals are uncertain and working in groups with expertise, or when arousal is at a moderate level.
Therefore, the correct answer to the question is c) both a and b, indicating that low performance is most likely when individual performance cannot be evaluated and when the task is relatively easy.