Q: 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 pilot study on the correlation between skin auto-fluorescence and serum antioxidant enzyme : skin auto-fluorescence negatively associated with levels of malondialdehyde?
Answer: We determined that skin AF intensity of the photo-protected area reflects intrinsic skin aging. In addition, degree of photo-aging could be indirectly inferred by skin AF of photo-exposed area and serum MDA level.
A:
yes