小强已经长大了，看见妈妈非常辛苦，就尝试着帮助妈妈做家务活．有一次，妈妈吃完饭后，他争着要刷碗，你能告诉他怎样才能确定碗洗干净了呢？

—        that he picked up French?

—It was in 1949          he traveled in France. 

A．Was it when; that

B．When was it; that

C．Was it when; when

D．When was it; when