【题目】To improve the quality of our products, we asked for suggestions ________ had used the products.
A. whoever B. who C. whichever D. which
在线课程【答案】A
【解析】
试题分析：句意：为了提高我们产品的质量，我们征求了任何用过的人的建议。这里是宾语从句，ask sb. for suggestions,这里缺sb.，whoever="anyone" who，句子用whoever来强调征求了很多人的意见，故选A。