39. In the 1950s, classroom violence ________. (A)) was something unheard of (B)) was by no means a rare occurrence (C)) attracted a lot of pubic attention (D)) began to appear in analysts’ data

30. It can be inferred from the passage that ________. (A)) killing foxes with poison is illegal (B)) limiting the fox population is unnecessary (C)) hunting foxes with dogs is considered cruel and violent (D)) fox-hunting often leads to confrontation between the poor and the rich