下列关于栓剂叙述中正确的有( )。

A．栓剂使用时塞入肛门6厘米处有利于药物吸收

B．pKa小于8.5的弱碱性药物，酸性药物pKa在4.5以上者可被黏膜迅速吸收

C．基质的溶解特性正好与药物相反时，有利于药物的释放与吸收

D．置换价是指药物的体积与基质重量的比值

E．可可豆脂具有多晶型，为避免晶型转变常缓缓加热升温，融化至2/3即停止加热至融化

The winner of the Nobel Prize in Literature 2012, Mo Yan , said he did not have high      for winning． Actually, he thought he only had a slim chance to win．

A．assumption

B．expectation

C．satisfaction

D．impression