下列有关单倍体的叙述中，不正确的是（）①未经受精的性细胞发育成的植物，一定是单倍体②

_________ more customers, many companies prefer to spend a lot of money in advertising.

A．Attract

B．Attracting

C．Attracted

D．To attract

33，38，67，35，70，45，这组数的平均数是______，中位数是______，它们相差______．

患者，男性，56岁。巩膜、皮肤黄染半月余。无腹痛，黄疸无波动。查体：皮肤巩膜黄染，肝肋下触及，右上腹扪及肿大胆囊，无触痛，无发热。

对鉴别黄疸性质最有意义的检查是（）

A.CT

B.腹部超声

C.肝功能测定

D.淀粉酶测定

E.ERCP

His grandfather died ____ the wound that the enemy soldier had given him .and then his grand-

mother died ____ hungry and cold.        

A．from,of

B．of,from

C．from,from

D．of.of