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.

[EX Q]: Question: Is the ribbon-associated protein C-terminal-binding protein 1 essential for the structure and function of retinal ribbon synapses?
Answer: Overall the results suggest that CtBP1 protein is not essential for the formation of functional ribbon synapses in the retina.
[EX A]: no

[EX Q]: 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.
[EX A]: no

[EX Q]: Question: Does preoperative mp-MRI of the prostate provide little information about staging of prostate carcinoma in daily clinical practice?
Answer: In routine clinical practice, mp-MRI at non-academic centers has very limited clinical value in predicting ECE and SVI. Our data support the current recommendations against the widespread preoperative use of mp-MRI because it is not adding reliable predictive information on the extent of prostate cancer.
[EX A]:
yes