Instructions: 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.
Input: Question: Are herpes simplex virus , cytomegalovirus , and papillomavirus DNA found in patients with chronic pelvic pain syndrome undergoing radical prostatectomy for localized prostate cancer?
Answer: A viral etiology could not be demonstrated in CPPS. In addition, no association of the viruses with prostate cancer could be found.
Output:
no