The little boy is dirty from head to foot because he in the mud all morning.
A. has played
B. is playing
C. has been playing
D. was playing
网友回答
A. has played
B. is playing
(答案→)C. has been playing
D. was playing
解析： 从is dirty from head to foot和all morning判断应用一直在玩。现在完成时态和现在完成进行时态都是说明动作由过去开始，该动作延续到现在。