連詞用法舉例...which one is correct,please?________ modeling busin

題目：

連詞用法舉例...which one is correct,please?________ modeling business is by no means easy to ge
Which one is correct,why,please?有2種答案,A,B,請翻譯你選擇的答案.
________ modeling business is by no means easy to get into,the good model will always be in demand.
A.While B.Since C.As D.If

解答：

A.while有「雖然」之意 翻譯到此句里就是「雖然.,但是好的模特還是總會被需要的.」
B.since有「因爲」之意,所以就是「因爲...,所以好的模特一直被需要」