Few businesses will voluntarily implement environmental rotection measures that benefit the public if those measures reduce profitability. Even though such measures may cost less to implement than the total value of their benefits to society, the company making the decision bears all of the cost and receives little, if any, of the benefit. For example, XYZ Corporation has for the last 10 years refused to install smokestack filters to reduce the air pollution emitted by its factory, claiming that the cost would be prohibitive. Therefore, if such measures are to be implemented to protect the environment, they must be initiated by government regulation or intervention.

The bolded portions of the argument above perform which of the following functions?

1. The first phrase states the conclusion, and the second provides evidence, the truth of which supports the validity of the conclusion
2. The first phrase states a premise supporting the conclusion, and the second provides evidence, the falsity of which would disprove the first phrase.
3. The first phrase describes a general principle, and the second provides evidence countering that principle.
4. The first phrase states a claim supporting the conclusion, but for which no evidence is given, and the second describes an example supporting the conclusion.
5. The first phrase states a generalization supporting the conclusion, and the second cites an example supporting that generalization.

[spoiler]OA is between D and E.
Provide your reasoning to choose one and to discard other.
Source : Princeton [/spoiler]