单选题
They crawled for the next three hours along a main road where a line of traffic was so tightly together that it was______almost stationary.
【正确答案】
D
【答案解析】解析：句意：接下来的三个小时他们在主路上缓慢挪动，这条堵塞的队伍蜿蜒绵长，好像所有车辆都是静止不动的。crowd“拥挤”；block“封锁”；assemble“组合”；wedge“挤进”。根据句意，本题答案为D。