问题补充：
They often have problems with.
A. what will they be able to do
B. what they will be able to do
C. that will they have to do
D. that will they have to do
答案：
A. what will they be able to do
(答案→)B. what they will be able to do
C. that will they have to do
D. that will they have to do
解析：句意：他们经常在他们将能做什么方面有问题。位于介词with后的宾语从句是特殊疑问句，其词序为：疑问词+主语+谓语+宾语，因此此处的宾语从句为what they will be able to do 。故选B。
