Which of the following most probably means what you hear

A．Everybody has opportunities if he is ready for them.

B．Some people have opportunities and are ready for them.

C．All people have opportunities, but only some people seize them.

D．Opportunities come to people when they are not ready.

江南某镇居民共饮一条河水，于7月中旬先后有近百人发热，均伴有乏力、纳差，部分病人腹泻或便秘。检查：大部分发热病人有肝脾肿大，少数病人前胸或上腹部有暗红色皮疹，怀疑为伤寒流行。

对正在发热病人进行哪项检查最有助于明确诊断（）

A.肥达反应

B.血培养

C.骨髓培养

D.大便培养

E.尿培养