The National Revolutionary Party boosted the Mexican economy by O privatizing the railroads and oil industry.
O nationalizing the railroads and oil industry.
O selling the railroads and oil industry.
O closing the railroads and oil industry.

b) nationalizing the railroads and oil industry

Explanation:

congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.