一道GWD题目，请NN指点！！！

The Environmental Protection Agency’s proposal to place restrictions on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, saying that the move will exacerbate the nation’s fuel supply problems.

1. on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, saying
2. on both diesel fuel and engines have sparked the oil industry to counterattack, and they say
3. on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, which says
4. both on diesel fuel and engines has sparked the oil industry to a counterattack, saying
5. both on diesel fuel and diesel engines have sparked the oil industry to counterattack, and it says

答案是C，我选A;

C中的which 可以修饰PROPOSAL, 也可以修饰OIL INDUSTRY，有歧义啊；

A中SAYING 可以表伴随，没有错啊？

请NN指点！

GMAT语法中which就近修饰，所以只能修饰OIL INDUSTRY

反而是伴随状语的使用会产生歧义，它可以修饰proposal 或者 oil industry