Given the task definition and input, reply with output. 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.

Question: Is rANK/OPG ratio of expression in primary clear-cell renal cell carcinoma associated with bone metastasis and prognosis in patients treated with anti-VEGFR-TKIs?
Answer: RANK/OPG ratio of expression in primary ccRCC is associated with BM and prognosis in patients treated with anti-VEGFR-TKIs. Prospective validation is warranted.
yes