According to 35 U.S.C. § 101, what can potentially be patented?

The reason why the selection highlighting new and useful processes, machines, and compositions of matter is correct lies in the foundational principles established by the U.S. patent law, particularly under 35 U.S.C. § 101. This statute explicitly outlines the categories of inventions that are eligible for patent protection.

Processes refer to methods of doing something, typically involving a series of steps; machines encompass tangible devices or apparatuses that perform specific functions; and compositions of matter cover chemical compounds, mixtures, or any manufactured composition. The phrase "new and useful" emphasizes that for an invention to be patentable, it must not only be novel but also provide some utility or practical benefit.

In contrast, the other choices do not align fully with the legal framework. While new and useful articles and services may be significant, the term "articles" can be ambiguous and may not encompass the precise definitions needed for patent eligibility. Moreover, services are generally not patentable under this statute, as they don't fit within the defined categories. The idea of "new and useful ideas" lacks the specificity needed for patentability as ideas themselves are abstract and not tangible inventions, thus failing to meet the requirements set forth in the statute.