问题
单项选择题
To improve the quality of our products, we asked for suggestions ______ had used the products.
A．whoever
B．who
C．whichever
D．which
答案
参考答案：A
解析： whoever相当于anyone who，引导宾语从句；who只能作主语，不能作ask的宾语；C和D不符合。故选A。