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 Input:
Question: Is vitamin D deficiency independently associated with greater prevalence of erectile dysfunction : The National Health and Nutrition Examination Survey ( NHANES ) 2001-2004?
Answer: In this cross-sectional analysis of a representative sample of U.S. men, vitamin D deficiency was associated with an increased prevalence of ED independent of ASCVD risk factors. Additional research is needed to evaluate whether treating vitamin D deficiency improves erectile function.

Ex Output:
yes

Ex Input:
Question: Does school-based physical activity compromise children 's academic performance?
Answer: The AS! BC model is an attractive and feasible intervention to increase physical activity for students while maintaining levels of academic performance.

Ex Output:
no

Ex Input:
Question: Does cD73 predict Favorable Prognosis in Patients with Nonmuscle-Invasive Urothelial Bladder Cancer?
Answer: High CD73 immunoreactivity was associated with favorable clinicopathological features. Furthermore, it predicts better outcome in the subgroup of pTa and pT1 tumors and may thus serve as additional tool for the selection of patients with favorable prognosis.

Ex Output:
yes