How long do copyrights last for works created on or after January 1, 1978?

The duration of copyright protection for works created on or after January 1, 1978, is indeed for the life of the author plus 70 years. This means that once an author passes away, their work remains protected by copyright for an additional 70 years. This extended term is designed to encourage creativity by providing the author—and their heirs—sufficient time to benefit financially from their work.

In cases where a work has multiple authors, the copyright lasts for the life of the last surviving author plus 70 years. If a work is created by a corporate entity, the copyright lasts for 95 years from publication or 120 years from creation, whichever is shorter, but this does not apply to individual authors.

The other possible durations of copyright mentioned do not align with the current copyright law, which has been standardized to the life of the author plus 70 years for individual authors, thus making the correct answer clear and definitive.