A deal is a deal—except, apparently, when Entergy is involved. The company, a major energy supplier in New England, provoked justified outrage in Vermont last week when it announced it was reneging on a longstanding commitment to abide by the state’s strict nuclear regulations.

    Instead, the company has done precisely what it had long promised it would not: challenge the constitutionality of Vermont’s rules in the federal court, as part of a desperate effort to keep its Vermont Yankee nuclear power plant running. It’s a stunning move.

    The conflict has been surfacing since 2002, when the corporation bought Vermont’s only nuclear power plant, an aging reactor in Vernon. As a condition of receiving state approval for the sale, the company agreed to seek permission from state regulators to operate past 2012. In 2006, the state went a step further, requiring that any extension of the plant’s license be subject to Vermont legislature’s approval. Then, too, the company went along.

    Either Entergy never really intended to live by those commitments, or it simply didn’t foresee what would happen next. A string of accidents, including the partial collapse of a cooling tower in 2007 and the discovery of an underground pipe system leakage, raised serious questions about both Vermont Yankee’s safety and Entergy’s management—especially after the company made misleading statements about the pipe. Enraged by Entergy’s behavior, the Vermont Senate voted 26 to 4 last year against allowing an extension.

    Now the company is suddenly claiming that the 2002 agreement is invalid because of the 2006 legislation, and that only the federal government has regulatory power over nuclear issues. The legal issues in the case are obscure: whereas the Supreme Court has ruled that states do have some regulatory authority over nuclear power, legal scholars say that Vermont case will offer a precedent-setting test of how far those powers extend. Certainly, there are valid concerns about the patchwork regulations that could result if every state sets its own rules. But had Entergy kept its word, that debate would be beside the point.

    The company seems to have concluded that its reputation in Vermont is already so damaged that it has nothing left to lose by going to war with the state. But there should be consequences. Permission to run a nuclear plant is a public trust. Entergy runs 11 other reactors in the United States, including Pilgrim Nuclear station in Plymouth. Pledging to run Pilgrim safely, the company has applied for federal permission to keep it open for another 20 years. But as the Nuclear Regulatory Commission (NRC) reviews the company’s application, it should keep in mind what promises from Entergy are worth.

答案精析：根据题干中的the Vermont case可定位至原文第五段第二句。该句中出现test，检验的内容是后面的how far those powers extend（这些权限能扩大到什么地步），those powers指代前文所说的各州在核能上的管理权限，故D选项为正确答案。

错项排除：安特吉公司已经宣布要违约，所以此次事件不会考验其履行承诺的能力，故A选项错误。B选项中的nature在文中没有体现，故错误。C选项主语张冠李戴，原文说的是states（各州）在核问题上有some regulatory authority（一些管理权威），并非the federal authority（联邦政府），故C选项错误。

长难句分析：The legal issues in the case are obscure: whereas the Supreme Court has ruled that states do have some regulatory authority over nuclear power, legal scholars say that Vermont case will offer a precedent-setting test of how far those powers extend.

本句为复合句，冒号前后为两个分句，前面的分句较为简单，是主系表结构，冒号后的句子则是whereas连接的并列句，表示前后句的转折关系。whereas后的分句中嵌套了that引导的宾语从句，说明裁定的内容，其中do have是强调。后面的分句主干是legal scholars say that…，是主谓宾结构，that引导的从句Vermont case…extend是say的宾语，其中of how far those powers extend是介词结构作后置定语，修饰test。

句意为：这一事件中的法律问题并不明朗：尽管最高法院已经裁定各州对核能也拥有某些监管权限，但这些权限究竟能扩大到什么地步，法律专家认为佛蒙特州的案件提供了可作为先例的测试。