________ Yao Ming has retired from the NBA，the pleasure we have got by watching him play basketball at home and abroad will last long.
A．Although B．If
C．Since D．Once
________ Yao Ming has retired from the NBA，the pleasure we have got by watching him play basketball at home and abroad will last long.
A．Although B．If
C．Since D．Once
A解析： 分析句子结构并结合句意可知，逗号前的内容在句子中作让步状语。A项意为“虽然”；B项意为“如果”；C项意为“自从，因为”；D项意为“一旦”。