Tim got up late this morning he had to go to school by taxi.A. orB. soC. andD. but

问题补充：

Tim got up late this morning, he had to go to school by taxi.

A. or

B. so

C. and

D. but

答案：

A. or

(答案→)B. so

C. and

D. but

解析：四个选项分别表示选择关系、因果关系、并列关系和转折关系，根据上下文Tim起迟了，所以不得不乘出租车去学校，可知此处是因果关系，选B.