Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
Q: Question: Is association between severe cerebral amyloid angiopathy and cerebrovascular lesions in Alzheimer disease a spurious one attributable to apolipoprotein E4?
Answer: Severe CAA confers a greater risk of VLs in AD, even within strata of APOE genotype. Therefore, the association between severe CAA and VLs in AD is not a spurious one owing to APOE4. Overall, our cases of AD with APOE4 do not seem to be a more "vasculopathic" subtype of AD. The mechanisms by which CAA produces VLs of various types need to be further elucidated, as these are probably important in producing the common entity of "mixed" AD/vascular dementia. Arch Neurol. 2000.
A:
no