---May I borrow your book Steve Jobs ?
--- you return it before Friday.
A. If only
B. Unless
C. On condition that
D. Now that
网友回答
A. If only
B. Unless
(答案→)C. On condition that
D. Now that
解析：考查连词。A但愿；B除非；C条件是；D既然。句意：——我可以向你借《乔布斯》的书吗？——条件是你在周五之前还。故C正确。