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: Is echium oil protective against weight loss in head and neck cancer patients undergoing curative radio ( chemo ) therapy : a randomised-controlled trial?
Answer: Echium oil effectively increased erythrocyte EPA and GLA FAs in H&N cancer patients. It failed however to protect against weight loss, or improve nutritional parameters.
A:
no