Which of the following is considered an early warning sign of Alzheimer's disease?

Impaired cognitive function serves as a significant early warning sign of Alzheimer's disease. This can manifest through difficulties with memory, problem-solving, language use, and the ability to perform familiar tasks. In the early stages of Alzheimer's, individuals may begin to notice subtle changes in their cognitive abilities, such as forgetting recent conversations or indecisiveness in daily activities. Recognizing these signs is crucial, as early intervention can lead to better management and possible slowing of disease progression.

In contrast, increased physical activity, consistent memory retention, and lifestyle stability are typically not associated with Alzheimer's disease. Physical activity can be beneficial for cognitive health and does not serve as a warning sign. Consistent memory retention suggests that cognitive function is intact, and lifestyle stability indicates that there are no significant changes that might alert one to cognitive decline. Therefore, recognizing impaired cognitive function is essential in identifying the onset of Alzheimer's disease.