Final answer:
A collection of ancient Roman poetry is least likely to be covered by US copyright law because it predates modern copyright laws and its authors are long deceased. Contemporary creative works and scientific articles would typically be protected.
Step-by-step explanation:
The item least likely to be covered by US copyright law is B) A collection of ancient Roman poetry. Copyright law protects original works of authorship, including literary, dramatic, musical, and other types of creative works. Given that ancient Roman poetry predates modern copyright laws by centuries and the authors are long deceased, it would not be eligible for copyright protection. In contrast, works by contemporary authors, new compositions by American artists, and scientific research articles, assuming they meet the criteria for originality and fixation, would typically be covered under copyright law, which lasts for the life of the author plus 70 years.