单选题 What can you do if the international line is engaged?

A、 Ask the operator to call you back later.
B、 Make a "person-to-person" call.
C、 Call back outside office hours.
D、 Walt and call again when the line is free.

【正确答案】 A

【答案解析】[解析] 事实细节题。从文章第二段最后一句话可知，If the international line is busy，you can reserve(留下)a call，explain the number you want and the operator will call you back when the line is free．要是占线的话，你可以留下电话，等空闲时接线员会通知你的。所以正确的答案为A。