In the case of Marbury v Madison the issue centered around William Marbury´s appointment was Justice of the Peace in the District of Columbia.
The president would be able to veto the bill that the Congress made and can just publicly say that the reason the veto is being done is because it violates the U.S. Constitution. The Supreme Court, on the other hand, could simply review it if a lawsuit about the law was filed, and then declare it unconstitutional.
The cause of the civil war was about no slave and for the USA to be free to all.
Both the Mauryan and Gupta empires were Hindu. That is why the answer to this question is letter C. Hinduism flourished and expanded throughout India. Aside from Hinduism, other religions such as Buddhism and Jainism were also part of the cultures of these empires.