However combinations or associations of the above description may now and then answer popular ends. They are likely in the course of time and things to become potent engines, by which cunning ambitious and unprincipled men will be enabled to subvert the power of the people and to usurp for themselves the reins of government. Destroying afterwards the very engines which have lifted them to unjust dominion.

In the above quote from Washington's Farewell Address (1797) what did he warn against?

a. Foreigners getting involved in American politics.
b. The creation of political parties.
c. The judicial branch.
d. State legislatures

a. Foreigners getting involved in American politics.        

Explanation:

The given speech was addressed by George Washington on his farewell speech which he gave during the end of his term in the fall of 1796. Washington was much worried about the politics of the future America. His main intension was to serve as the guide to the future statecraft for his successors in the office ad also for the American citizens.

In his farewell speech, Washington warned America and its people not to make permanent alliance with other foreign nations but to rely on the temporary alliances with them for any emergency. He was frustrated with interference of the French government in the politics of the US.

So in his speech he warned against the foreigners of getting involved in the politics of America.