【题目】As you can see，the number of cars on our roads ________ rising these days.
A.was keeping
B.keep
C.keeps
D.were keeping

【答案】C
【解析】句意：正如你能看见的，道路上汽车的数量这些天一直在增长。keep doing一直做，the number of …的数量，做主语谓语用单数。所以答案是C。