【题目】Lisa has had to stop doing all the gardening recently,______her back problem.
A.on account of
B.in response to
C.with regard to
D.by means of

【答案】A
【解析】考查介词短语。句意：丽萨最近不得不停止所有的园艺工作，因为她背部出了毛病。A. on account of “由于”； B. in response to“回答、响应”；C. with regard to “关于”； D. by means of “通过”。根据语境是由于背疼的缘故。故选A。