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 elevated preoperative plasma D-dimer level a useful predictor of chemoresistance and poor disease outcome for serous ovarian cancer patients?
Answer: Elevated preoperative plasma D-dimer levels were associated with chemoresistance and poor disease outcome in serous ovarian cancer patients. Further validation of this easily available parameter as a promising prognostic biomarker for patients with SOC in prospective studies should be encouraged.
A:
yes