Which of the following is NOT a characteristic of Alzheimer's disease?

Improvement of cognitive function is indeed not a characteristic of Alzheimer's disease. Alzheimer's involves a gradual decline in cognitive abilities, including memory, reasoning, and judgment. This deterioration manifests in various ways, such as confusion, forgetfulness, and difficulty with problem-solving tasks.

In contrast, the other characteristics listed reflect the progression of Alzheimer's. Destruction of memory is a fundamental aspect as the disease primarily affects memory processes, often leading to significant gaps in personal history and daily tasks. Deterioration of mental functions encompasses the broader cognitive decline seen as the disease progresses, impacting language, spatial awareness, and everyday functioning. Progressive memory loss typically characterizes the illness, marking its irreversible nature and the challenges faced by both patients and caregivers. Therefore, while Alzheimer's leads to a host of cognitive challenges, it does not lead to improvement, making the identification of this option as the correct response valid.