题目选项分析

his is a bit hard to see in this particular sentence, so here's an analogy (which i'm making up on the spot - not part of an official question):
as small a collection as three pirated albums has occasionally drawn the attention of the recording industry.
in this case, 'collection', not 'albums', is the subject of 'has drawn' (which can be inferred from the fact that 'has' is singular).
this is the case because this sentence is equivalent to the following rearranged version:
a collection as small as three pirated albums has occasionally drawn the attention of the recording industry.
the same reasoning applies here; you're looking for idiomatic usage that agrees with 'risk', not 'chance'.
the last poster is incorrect in this particular scenario, because 'chance to' is NOT used when 'chance' refers to a mathematical probability (as it does in this context). in the case of mathematical probabilities, you can only use 'chance of'.
for instance, you can't say this treatment has a 70% chance to cure the disease; you have to say chance of curing.

1. chance 表达几率的时候用of ....的几率 chance of causing cancer 导致癌症的几率

1 present risk
2 risk of doing sth