—There were already five people in the car but they managed to t

—There were already five people in the car but they managed to take me as well.
—It ______ a comfortable journey.
A、can’t be
B、shouldn’t be
C、mustn’t have been
D、couldn’t have been
【正确答案】：D
【题目解析】：由题意可知被猜测的时间是过去，有客观事实根据there were already five people...take me as well，猜测语气要求最强，所以正确选项是D。