Today,we will discuss a number of situates ---beginners of E

1. 答案：A.
2. 翻译：今天,我们将讨论许多英语初学者没能成功恰当地处理的情况.
3. 解释：
1）先行词是situations,它在定语从句中做deal with的宾语.
situations是物,所以只能用关系代词which代替它.
deal with中的with是介词,其后必须加上宾语,不能缺少.
2）即：which beginners of English fail to deal with properly
= beginners of English fail to deal with (which) properly
= beginners of English fail to deal with (the situations) properly.