题目内容：

英语science and technology 作主语
China sent up ShenzhouVII manned spaceship into space successfully,which shows science and technology _____ rapidly in China.
A.have been developing B.develops C.is developing D.has developed
我不明白为什么是选这个时态,而不选c,不是可以表示正在发展变化的过程吗?还有一个问题就是science and technology 做主语是应不应该看成是一个整体表示科技呢,谓语用单数还是复数