A state legislature received complaints from traffic accident victims who, in the days immediately following their accidents, had received unwelcome and occasionally misleading telephone calls on behalf of medical care providers. The callers warned of the risks of not obtaining prompt medical evaluation to detect injuries resulting from accidents and offered free examinations to determine whether the victims had suffered any compensable injuries. In response to these complaints, the legislature enacted a law prohibiting medical care providers from soliciting any accident victim by telephone within 30 days of his or her accident. Which of the following arguments would be most helpful to the state in defending the constitutionality of the law?

a. Because the law regulates only commercial speech, the state need only demonstrate that the restriction is rationally related to achieving the state's legitimate interests in protecting the privacy of accident victims and in regulating the medical profession.
b. The law is a reasonable time, place, and manner regulation.
c. The state has substantial interests in protecting the privacy of accident victims and in regulating the practice of medical care providers, and the law is narrowly tailored to achieve the state's objectives.
d. Because the commercial speech that is the subject of this law includes some speech that is misleading, the First Amendment does not limit the power of the state to regulate that speech.