Final answer:
The Defense of Marriage Act challenged the Constitution's 'full faith and credit' clause, which requires states to recognize legal documents from other states. The Tenth Amendment is the source of powers reserved to the states. The Supreme Court ruled DOMA unconstitutional, reinforcing the Fourteenth Amendment's Equal Protection Clause.The correct option is d.
Step-by-step explanation:
The Defense of Marriage Act (DOMA) provided a challenge to the Constitution's full faith and credit clause. This clause, found in Article IV, Section 1 of the Constitution, requires states to accept court decisions, public acts, and contracts of other states, which includes marriage certificates. DOMA, enacted in 1996, stated that no state needed to recognize a marriage between persons of the same sex even if it was recognized in another state. This act was later found to be unconstitutional as it violated the Equal Protection Clause of the Fourteenth Amendment, as decided by the Supreme Court in the Obergefell v. Hodges case in 2015.
The source of powers "reserved" to the states, which refers to those powers not delegated to the federal government, is identified in the Tenth Amendment.
In conclusion, challenges to same-sex marriage and the Defense of Marriage Act brought the full faith and credit clause to the forefront, with the Supreme Court's ruling in Obergefell v. Hodges ultimately reinforcing the equal protection under the Fourteenth Amendment.