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.

[Q]: Question: Do progesterone receptor and PTEN expression predict survival in patients with low- and intermediate-grade pancreatic neuroendocrine tumors?
Answer: Combined immunohistochemical assessment of PR and PTEN may help identify a small subset of PanNETs with more aggressive behavior and may aid in risk stratification.
[A]: yes


[Q]: Question: Is pseudomonas aeruginosa in CF and non-CF homes found predominantly in drains?
Answer: These findings implicate drains as important potential sources of P. aeruginosa infection. They suggest that maximizing P. aeruginosa control efforts for drains would reduce exposure with minimal extra burden to CF patients and families.
[A]: yes


[Q]: Question: Is serum vitamin D associated with non-alcoholic fatty liver disease in Chinese males with normal weight and liver enzymes?
Answer: The present study demonstrated that serum 25(OH)D3 levels were inversely associated with NAFLD, even in subjects with normal total body fat, suggesting a potential role of lower levels of vitamin D in the occurrence and development of NAFLD.
[A]:
yes