This constitution, and the laws of the united states which shall be made in pursuance thereof; and all treaties made, or which shall be made, under the authority of the united states, shall be the supreme law of the land; and the judges in every state shall be bound thereby, any thing in the constitution or laws of any state to the contrary notwithstanding.1
this part of the constitution allows:
a. state laws to stand even when they contradict federal laws. b. state laws to be declared unconstitutional. c. states to prevent the expansion of other states' businesses into their states. d. the federal government to intervene in state income tax laws.

The answer is state laws to be declared unconstitutional for APEX

Option B.The part of the Constitution showed in the question allows state laws to be declared unconstitutional.

Explanation:

Article VI, Clause 2 of the United States Constitution is also known as the "Supremacy Clause". The Supremacy Clause is considered the most important guarantor of national union, by stating that the Constitution, federal laws and treaties made under its authority constitute the "supreme law of the country", and therefore state laws are bound by them. In summary, the Supreme Clause states officially that state laws can be declared unconstitutional if found to be in detriment with federal laws, treaties or the Constitution.

1) union forces launched a surprise attack.

2) more confederate troops arrived by train.

3) union forces retreated.

it was douglas macarthur..