Many psychologists and sociologists now contend that the deliberate and even brutal aggression integral to some forms of competitive athletics increase the likelihood of imitative violence that erupts among crowds of spectators dominated by young adult males.
我对答案没什么问题,但是对于integral to 这个东西有些疑问,请问在这个结构里:A integral to B integral to 是什么性质?连词如and 还是介词如with?我看到有的例句中写道:A is integral to B 表示A是B的一部分,感觉不像是介词性质。那么怎么能判断出aggression是中心词呢?