Question

a general limitation on the power of the president is the possibility of impeachment. the ability to grant pardons. the ability to make treaties. the threat of treason.

Explanation:

Impeachment is a process to remove a president from office for misconduct, thus limiting presidential power. The ability to grant pardons and make treaties are powers of the president, not limitations. Treason is a crime, not a general limitation on power in the way impeachment is.

Answer:

the possibility of impeachment.