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: Do allergens of Epicoccum nigrum grown in different media for quality source material?
Answer: The day-13 culture of EN in SBY was the most potent and may be selected for preparing EN extracts for diagnosis of allergy and future studies.
[EX A]: yes

[EX Q]: Question: Are arterial stiffness and pulse wave reflection increased in patients suffering from severe periodontitis?
Answer: The results of this study confirm the association between periodontal inflammation and increased cardiovascular risk shown by impaired vascular health in case of severe periodontitis. As impaired vascular health is a common finding in patients suffering from severe periodontal disease a concomitant routine cardiovascular evaluation may be advised.
[EX A]: yes

[EX Q]: Question: Are vitamin D deficiency and low ionized calcium linked with semen quality and sex steroid levels in infertile men?
Answer: Infertile men with vitamin D deficiency had lower sperm motility, total numbers of motile sperm, Inhibin B, sex-hormone-binding-globulin (SHBG) and testosterone/estradiol ratio, but higher levels of free sex steroids, than infertile men with normal vitamin D levels.
[EX A]:
yes