题目内容：

What type of mobile phone do you want to have?Something big?Well,it __ be big-that'not important
A mustn't
B needn't
C can't
D won't

优质解答

你想要那种类型的手机?大个的吗?
嗯,不必要是大的,那不重要.
所以根据语气推测,应该选B.