instruction:
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.
question:
Question: Is tobacco smoking associated with decreased semen quality?
Answer: Results demonstrated a decline in semen quality in a dose dependent tobacco smoking manner.
answer:
yes


question:
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.
answer:
no


question:
Question: Is sofosbuvir and ribavirin for 6 weeks effective among people with recent hepatitis C virus infection : The DARE-C II study?
Answer: Six weeks of sofosbuvir and ribavirin was safe and well tolerated, but efficacy was suboptimal; further research is needed to determine whether more potent interferon-free direct-acting antiviral regimens will allow treatment duration to be shortened in recent, predominantly asymptomatic HCV infection. (Hepatology 2016;64:1911-1921).
answer:

no