Final answer:
Polyphagia associated with diabetes mellitus does not mean the patient is extremely thirsty. It actually means excessive hunger.
Step-by-step explanation:
The statement that polyphagia associated with diabetes mellitus means that the patient is extremely thirsty is False.
Polyphagia is actually excessive hunger, not thirst. It is one of the early manifestations of diabetes, along with excessive urination and excessive thirst. Excessive blood glucose levels in diabetes make it difficult for cells to access glucose, leading to persistent hunger.