A 35-year old man with Down's syndrome dies of acute lymphoblastic leukemia. Gross examination of the patien,s brain at autopsy shows mild microcephaly and underdevelopment of the superior temporal gyri. Histologic examination would most likely show which of the following neuropathologic changes?
A) Negri bodies
B) Neurofibrillary tangles
C) Spongiform encephalopathy
D) Lewy bodies