①能够产生酶的细胞都有分泌功能
②酶的基本单位都是氨基酸
③胰岛素与呼吸酶可来自于同一个细胞
④酶是生物催化剂
A:1个
B:2个
C:3个
D:4个
下列对落后文化、腐朽文化叙述不正确的是( )
Diaoyu Islands __________ China ever since ancient times.
— The box is too heavy to carry. What's in it?
— Jack _______ it with many books.