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: Is a high body mass index in esophageal cancer patients associated with adverse outcomes following esophagectomy?
Answer: A high BMI is not associated with increased overall morbidity following esophagectomy; moreover, it is associated with decreased incidence of chylothorax. The better overall survival in patients with high BMI compared with those with low BMI might be due to a relatively low pathological stage. A high BMI should therefore not be a relative contraindication for esophagectomy.
Example Output: no

Example Input: Question: Does in a safety net population HPV4 vaccine adherence worsen as BMI increases?
Answer: Obesity, as well as gravidity and Hispanic race, are risk factors for lack of HPV4 vaccine adherence among young females in a safety net population.
Example Output: yes

Example Input: Question: Do serum testosterone levels decrease in middle age in women with the polycystic ovary syndrome?
Answer: Hyperandrogenism partly resolves before menopause in women with PCOS. This change may explain the tendency of women with PCOS to cycle regularly as they grow older. Testosterone levels remain elevated in older women with PCOS, however, and may contribute to their increased risk for cardiovascular disease, endometrial cancer, and other diseases.
Example Output:
yes