The best response that explains the limits to the power of the executive branch established in the U.S. Constitution is:
The president is elected for a four-year term, and one person can have only two terms as president.
This response highlights the constitutional limits on the duration of a president's tenure, which is a key aspect of checks and balances within the U.S. government. It reflects the framers' intent to prevent any individual from holding excessive power for too long.