问题
选择题
______ they grow they make sure that what is left in the ground after harvesting______ a natural fertilizer for the next year’s crop.
A．Whatever; become
B．Whichever; become
C．Whatever; becomes
D．Whichever; becomes
答案
答案：C
题目分析：考查状语从句和主谓一致。句意：无论他们种什么，他们确信在了收获后留在地里的都会成为为了来年的收成的一中天然的肥料。根据：whichever无论哪一个（有固定范围），而本句没有范围，所以排除B和D，第二个空根据主语是what从句，谓语动词有表语而定，表语a natural fertilizer f，单数，所以一个是becomes ,所以C正确。
