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.

[EX Q]: Question: Does revaccination with Bacillus Calmette-Guerin ( BCG ) vaccine reduce morbidity from malaria in African children?
Answer: We found no evidence that BCG revaccination reduces morbidity from malaria.
[EX A]: no

[EX Q]: Question: Does usability testing found problems for novice users of pediatric portals?
Answer: Despite parental involvement and prior heuristic testing, scenario-based testing demonstrated difficulties in navigation, medical language complexity, error recovery, and provider-based organizational schema. While such usability testing can be expensive, the current study demonstrates that it can assist in making healthcare system interfaces for laypersons more user-friendly and potentially more functional for patients and their families.
[EX A]: yes

[EX Q]: Question: Does metformin ameliorate insulin resistance in L6 rat skeletal muscle cells through upregulation of SIRT3?
Answer: Upregulated SIRT3 is involved in the pharmacological mechanism by which metformin promotes glucose uptake. Additionally, SIRT3 may function as an important regulator of oxidative stress and a new alternative approach for targeting insulin resistance-related diseases.
[EX A]:
yes