Mary, a 79-year-old patient, is brought to your office by her daughter, who reports that her mother has been exhibiting several concerning symptoms over the past year. Comprehensive questioning reveals that her symptoms are: trouble remembering familiar things, such as telephone numbers commonly dialed; not recognizing some close family members who visit often; and difficulty performing writing tasks. The patient's motor function appears to be unaffected. Although not definitive, these symptoms are most likely indicative of which type of dementia? A. Alzheimer's disease
B. Dementia with Lewy bodies
C. Huntington's disease
D. Frontotemporal dementia