I _________ my homework last night when I heard a loud knock on the door.[ ]

A. did

B. was doing

C. have done

D. had done

下列词语中加点的字，读音全都正确的一组是( )。

A．泊车(bó)
称心(chèn)
唱主角(jiǎo)
弹丸之地(dàn)
B．苍穹(qióng) 掺和(cān)
单行本(xíng)
不偏不倚(yǐ)
C．梦魇(yǎn)
本埠(bù)
黑魆魆(bù)
燕颔虎颈(hàn)
D．祝祷(dǎo)
鞭笞(chī)
便利店(biàn)
名噪一时(cào)