The nullification crisis was caused by which political idea?

a. constitutionalism
b. checks and balances
c. separation of powers
d. states’ rights

The Nullification Crisis was caused by the political idea of the states’ rights.

Explanation:

In the initial decades after the US declared independence, the issue of trade and tariffs kept on surfacing for a long time. To get rid of the tariffs imposed by the union, the 'state of South Carolina' passed an ordinance to declare the tariffs of the union 'null and void' within the boundaries of the state. This gave birth to growing 'tensions' between the 'union' and the 'state of South Carolina' over the issue of states' right to pass such an ordinance. The crisis came to be known as the 'Nullification Crisis'.