①作为学生应认真完成各科作业 ②作为朋友要讲哥们儿义气
③作为公民要遵守国家法律 ④作为行人要避免惹是生非
A:①②
B:①④
C:①③
D:②③
There __________ an elephant, two monkeys and three snakes in the zoo.