The U.S. Postal Service (USPS) continues to bleed red ink. It reported a net loss of $5.6 billion for fiscal 2016, the 10th straight year its expenses have exceeded revenue. Meanwhile, it has more than $120 billion in unfunded liabilities, mostly for employee health and retirement costs. There are many bankruptcies. Fundamentally, the USPS is in a historic squeeze between technological change that has permanently decreased demand for its bread-and-butter product, first-class mail, and a regulatory structure that denies management the flexibility to adjust its operations to the new reality.

    And interest groups ranging from postal unions to greeting-card makers exert self-interested pressure on the USPS’s ultimate overseer—Congress—insisting that whatever else happens to the Postal Service, aspects of the status quo they depend on get protected. This is why repeated attempts at reform legislation have failed in recent years, leaving the Postal Service unable to pay its bills except by deferring vital modernization.

    Now comes word that everyone involved—Democrats, Republicans, the Postal Service, the unions and the system’s heaviest users—has finally agreed on a plan to fix the system. Legislation is moving through the House that would save USPS an estimated $28.6 billion over five years, which could help pay for new vehicles, among other survival measures. Most of the money would come from a penny-per-letter permanent rate increase and from shifting postal retirees into Medicare. The latter step would largely offset the financial burden of annually pre-funding retiree health care, thus addressing a long-standing complaint by the USPS and its unions.

    If it clears the House, this measure would still have to get through the Senate—where someone is bound to point out that it amounts to the bare, bare minimum necessary to keep the Postal Service afloat, not comprehensive reform. There’s no change to collective bargaining at the USPS, a major omission considering that personnel accounts for 80 percent of the agency’s costs. Also missing is any discussion of eliminating Saturday letter delivery. That common-sense change enjoys wide public support and would save the USPS $2 billion per year. But postal special-interest groups seem to have killed it, at least in the House. The emerging consensus around the bill is a sign that legislators are getting frightened about a politically embarrassing short-term collapse at the USPS. It is not, however, a sign that they’re getting serious about transforming the postal system for the 21st century.

答案精析：文章开头提到美国邮政管理局面临着财政危机，而原因一直到首段的最后一句才给出：一方面，技术变革持续地降低了其支柱产品——特快邮件的需求；另一方面，管理机构缺乏灵活性，不能根据新形式调整运营。由此可知，选B。

错项排除：第一段提到美国邮政管理局有超过1200亿美元的债务，主要是由于员工健康和退休费用导致，这跟不平衡预算不是一个概念，A错。原文说到技术变革，但并没有说美国邮政管理局会进行技术升级，C错。原文没有提到银行，更不可能有资助，D错。

长难句分析：Fundamentally, the USPS is in a historic squeeze between technological change that has permanently decreased demand for its bread-and-butter product, first-class mail, and a regulatory structure that denies management the flexibility to adjust its operations to the new reality.

句子主干是the USPS is in a historic squeeze。between的两个宾语是technological change和a regulatory structure，它们后面都为that引导的定语从句，起到补充说明的作用。第一个定语从句中的first-class mail是its bread-and-butter product的同位语。

句意为：从根本上说，美国邮政管理局正处在历史性的压力之下：一方面，技术变革持续地降低了其支柱产品——特快邮件的需求；另一方面，管理机构缺乏灵活性，不能根据新形式调整运营。