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.

Input: Consider Input: Question: Does [ Histology accurately predict the clinical behaviour of bronchopulmonary carcinoids - results from an Icelandic population-based study ]?
Answer: BPCs usually behave as benign neoplasms, with excellent long-term survival after surgical removal. Metastases are more common in patients with atypical histology (40%), and their survival is worse. However patients with typical histology can metastasize (14.8%) and die from the disease. Therefore, histology (typical vs. atypical) can not be used with certainty to predict the clinical behaviour of these tumors.

Output: no


Input: Consider Input: Question: Is alloantigen-driven T cell death mediated by Fas ligand and tumor necrosis factor-alpha essential for the induction of allograft acceptance?
Answer: These data indicate that: (1) FasL and TNFalpha expression are not obligatory for the induction of long-term allograft acceptance by CTLA4Ig and (2) FasL- and TNFalpha-independent death pathways contribute to alloantigen-driven T cell apoptosis.

Output: no


Input: Consider Input: Question: Do elevated depression symptoms predict long-term cardiovascular mortality in patients with atrial fibrillation and heart failure?
Answer: Elevated depression symptoms are related to cardiovascular mortality even after adjustment for other prognostic indicators in patients with comorbid AF and CHF who receive optimized treatment. Unmarried patients are also at increased risk. Mechanisms and treatment options deserve additional study.


Output: yes