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: Does helicobacter pylori infection in Mongolian gerbils initiate hematological diseases?
Answer: A single H. pylori infection is insufficient to cause onset of ITP or IDA and other factors may be required for disease onset.

Ex Output:
no


Ex Input:
Question: Is visceral pleural invasion a significant prognostic factor in patients with a part-solid lung cancer?
Answer: VPI may not contribute to the prognosis of patients with part-solid nodules. Thus, upgrading of the TNM stage on the basis of VPI should be carefully considered in these patients.

Ex Output:
no


Ex Input:
Question: Is intrathecal addition of morphine to bupivacaine the cause of postoperative nausea and vomiting?
Answer: Administration of metoclopramide did not reduce the overall incidence of PONV. Our study shows no relationship between the use of intrathecal morphine and the incidence of PONV during the first 24 hours postoperative.

Ex Output:

no