Final answer:
The Task Complexity principle in Locke and Latham's Goal Setting Theory involves motivation and performance on complex and difficult tasks.
Step-by-step explanation:
The Task Complexity principle in Locke and Latham's Goal Setting Theory involves the idea that when a task is complex and difficult, individuals feel more motivated to contribute their input and perform well on the challenging project. When the task is difficult, there is less pressure to do well and individuals experience less anxiety or arousal. This relaxed state allows individuals to perform their best.