--- Betty, could you answer my question?
--- Sorry, Mr. Green. I didn’t hear you. I about something else.
A. was thinking
B. am thinking
C. think
D. thought
网友回答
(答案→)A. was thinking
B. am thinking
C. think
D. thought
解析：句意：贝蒂，你能回答我的问题吗？——抱歉，格林老师。我没听清。我（刚才）正在想其它事情。结合语境可知下文指的是刚才正在进行的动作，故用过去进行时态。选A。