Question

       you eat the correct food          be able to keep fit and stay healthy.

A．Unless; will you	B．Only if; you will
C．Only if; will you	D．Unless; you will

Answer 1

C

试题分析：句意：只有如果你吃了适当的食物你才能保持健康。Only+状语从句放在句首的时候，句子用部分倒装，助动词will放在主语前面，unless“除非，如果不”，不符合句意。选C。