(单选题)

both sides accept the agreement a lasting peace be established in this region.

A.Only if, will

B.If only, would

C.Should, will

D.Unless, would

参考答案：A

参考解析：

考查only+状语位于句首的倒装。句意：只有双方都接受这份协议，该地区才能保持持久和平。only if意为“只有……才……”；if only意为“要是……就好了”，常用与虚拟语气，用陈述语气；Should位于句首常用与虚拟语气，用陈述语气；unless意为“除非”，用陈述语气；根据后半句“______ a lasting peace be established…”是部分倒装的结构，only放在了句首，且强调的是状语，后面的主句使用部分倒装的形式。故选A。

知识点：

______ both sides accept the agreement ______ a lasting peace be established in this region.

both sides accept the agreement a lasting peace be established in this region.