关于免疫耐受的叙述,下列哪项是错误的()
A.可天然获得
B.可后天获得
C.可长期存在
D.是一种免疫无应答状态
E.无抗原特异性
参考答案:E
She was such a proud person that she would die ____ she would admit she was wrong.
A.rather than
B.until
C.after
D.before
原料的族组成一般指(),(),()。