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 botulinum toxin B increase mouth opening in patients with spastic trismus?
Answer: Botulinum toxin serotype B injections into the masseter muscles effectively reduce hypertonia and provide for better mouth opening, thereby contributing to a positive and desired clinical goal.
Example Output: yes

Example Input: Question: Is cardiovascular variability similarly altered in coronary patients with normal left ventricular function and in heart failure patients?
Answer: Our study shows that in coronary patients with no MI and no left ventricular dysfunction, there is a profound alteration of both HR and BP variability as in CHF patients, presumably because of a marked impairment of the autonomic modulation of the heart and blood vessels.
Example Output: yes

Example Input: Question: Does the CC-genotype of the cyclooxygenase-2 gene associate with decreased risk of nasopharyngeal carcinoma in a Tunisian population?
Answer: We conclude that the CC-genotype and C allele of cox-2 T8473C gene polymorphism are associated with decreased risk of nasopharyngeal carcinoma in a Tunisian population.
Example Output:
yes