PREP 1题，to的疑惑

The Environmental Protection Agency frequently puts mandatory controls on toxic substances that present as little risk as one in a million chances to cause cancer. A

(A) as little risk as one in a million chances to cause

(B) as little risk as one chance in a million of causing

(C) as little risk as one chance in a million that it will cause

(D) a risk as little as one chance in a million for causing

(E) a risk as little as one chance in a million for it to cause

这道题目在AB之间选择。 不选择A的原因是因为介词to 是表示目的从而不好，还是在说比例的时候有问题，请牛牛帮忙， 答案是B

risk的用法是：risk of doing, 而risk to do 不对。in a million 是修饰one chance， 和of causing 没有关系