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.

Example Input: Question: Does the extent of lymphadenectomy for pTXNO prostate cancer affect prostate cancer outcome in the prostate specific antigen era?
Answer: The extent of lymphadenectomy does not appear to affect prostate cancer outcome in lymph node negative cases. This includes patients with high preoperative PSA, high pathological grade and extracapsular disease. These results suggest that under staging is not present in apparently node negative cases with limited lymphadenectomy and, even if present, its impact on outcome is likely to be negligible.
Example Output: no

Example Input: Question: Does exacerbation of headache during dihydroergotamine for chronic migraine alter outcome?
Answer: After controlling for nausea and other factors, headache exacerbation with DHE infusions is not an independent predictor of poor headache outcome and clinicians should not interpret its presence as a reason to stop treatment. The focus of management should be on controlling nausea as it is the most important modifiable factor in achieving a good headache outcome with an inpatient course of IV DHE for chronic migraine.
Example Output: no

Example Input: Question: Is assortative mating among Lake Malawi cichlid fish populations simply predictable from male nuptial colour?
Answer: We suggest that non-visual cues, such as olfactory signals, may play an important role in mate choice and behavioural isolation in these and perhaps other African cichlid fish. Future speciation models aimed at explaining African cichlid radiations may therefore consider incorporating such mating cues in mate choice scenarios.
Example Output:
no