Answer:
(A) Free Exercise Clause of the First Amendment
(B) In Wisconsin v. Yoder, the Supreme Court held that Wisconsin's compulsory school attendance law violated the Free Exercise Clause in the context of Amish parents who refused to send their children to public school after 8th grade. This is because Amish religion requires them to isolate themselves and attending public school beyond 8th grade would violate their religious beliefs. However, in Oregon v. Smith, the Supreme Court held that the Free Exercise Clause did not excuse individuals from complying with neutral and generally applicable laws, especially ones pertaining to drug use. The law they upheld was one that prohibited the use of peyote even in religious ceremonies.
C) Members of the state legislature who disagreed with the decision in Oregon v. Smith could try to pass a law that exempted religious use of peyote from the state's drug laws or impose a less burdensome restriction on the use of peyote in religious ceremonies.