—I’ve read another book this week.

—Well, maybe _______ is not how much you read but what you read that is important.

A．this

B．that

C．there

D．it

脊髓亚急性联合变性：（）

A.常由叶酸缺乏所致

B.以皮质脊髓束和脊髓丘脑束受损为主

C.常累及脑神经

D.括约肌障碍出现较晚

E.极少出现精神症