I’ve already forgotten　　　　you bought the dictionary.

A．that it was when

B．that was it when

C．when was it that

D．when it was that

苯丙氨酸-4-羟化酶缺乏()
鸟苷三磷酸环化水合酶缺乏()
6-丙酮酰四氢生物喋呤合成酶缺乏()
二氢生物喋呤还原酶缺乏()

A．喋呤总量增加，新喋呤/生物喋呤正常

B．喋呤总量增加，四氢生物喋呤减少

C．喋呤总量增加，新喋呤/生物喋呤增高

D．喋呤总量减少

E．喋呤总量增加，四氢生物喋呤增加