题目内容：
Which statement expresses an opinion?（）
A.Online shopping is now replacing shopping in store.
B.In the first place, television is not only a convenient source of entertainment, but also a comparatively cheap one.
C.All they have to do is press a button, and they can see plays, films, and shows of every kind, not to mention the latest football match.
D.Some researchers hold the belief that the brain is so complex and mysterious that we will never be able to fully understand it.
参考答案：