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.

Example Input: Question: Are immunologic marker paths for seroconversion : single determinations of immunoglobulin A and beta 2-microglobulin adequate to estimate time of HIV infection . Multicohort Analysis Project Workshop . Part II?
Answer: Further study of how serum IgA reflects HIV infection and careful clinical and statistical assessment of reduced beta 2M from 5 or 6 years after HIV infection are needed. The dependence of marker paths on mode of HIV transmission suggests that sexual transmission may have implications for HIV disease progression. The feasibility of using serum IgA and beta 2M, evaluable in single stored blood samples, to estimate time of HIV infection has been set back by our results.
Example Output: no

Example Input: Question: Do human umbilical cord-derived mesenchymal stem cells protect against experimental colitis via CD5 ( + ) B regulatory cells?
Answer: HUC-MSCs protected against experimental colitis by boosting the numbers of CD5(+) B cells and IL-10-producing CD5(+) Bregs, and correcting Treg/Th17/Th1 imbalances.
Example Output: yes

Example Input: Question: Does early aggressive nutrition enhance language development in very low-birthweight infants?
Answer: This study demonstrates the importance of the protein and energy intakes in VLBW infants in the first week of life not only for growth but also for better language development.
Example Output:
yes