A 35-year-old man with Down syndrome dies of acute lymphoblastic leukemia. Gross examination of the patient’s brain at autopsy shows mild microcephaly and underdevelopment of the superior temporal...

A 35-year-old man with Down syndrome dies of acute lymphoblastic leukemia. Gross examination of the patient’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) AA amyloidosis

(B) Lewy bodies

(C) Negri bodies

(D) Neurofibrillary tangles

(E) Spongiform encephalopathy