Final answer:
The law that would most likely be overturned based on the Supreme Court's decision in Reed v. Reed is a law that prohibits individuals under the age of 21 from purchasing alcohol, since Reed v. Reed involved the Equal Protection Clause of the Fourteenth Amendment which prevents differential treatment based on sex.
Step-by-step explanation:
Based on the Supreme Court's decision in Reed v. Reed, the law that would most likely be overturned is a law that prohibits individuals under the age of 21 from purchasing alcohol. Reed v. Reed was a landmark case that held that the Equal Protection Clause of the Fourteenth Amendment prevents differential treatment based on sex, thereby subjecting such laws to scrutiny under the Constitution. Given this precedent, the case most relevant to Reed v. Reed would be one that involves differential treatment based on an inherent characteristic, such as gender.
In contrast, the other laws listed do not directly pertain to gender discrimination. For example, a law requiring a literacy test to vote (a literacy test) has been deemed illegal when it has been used to disenfranchise certain groups, but this pertains to a different area of constitutional law, revolving around the Fifteenth Amendment and the Voting Rights Act of 1965, rather than gender discrimination. Similarly, laws related to age restrictions for alcohol purchase (the regulation of age restrictions) are often justified under the states' rights to protect the health and safety of their populations, and licensure requirements for certain professions are seen as a legitimate exercise of state power to ensure professional competence.