On account of the difference between openness and closeness of sentence structure, which of the following Chinese versions do you think is better?Can you answer a question which I want to ask and which is puzzling me?
选项：

A:我有一个问题弄不懂， 想请教你，你能回答吗？;
B:你能回答一个我弄不懂而又想问你的问题吗？;
C:我有一个弄不懂而又想问你的问题。你能回答吗？;
D:你能回答一个我想问你的又弄不懂的问题吗？