Which of the following is not a duty of the US president?

AAppoint justices to the Supreme Court.
BEnforce and execute federal laws.
CPropose a budget to Congress.
DDetermine the constitutionality of laws.

Verified Answer :

The US president does not determine the constitutionality of the laws: this is the task of the Supreme Court.

This has to do with the separation of powers: the president belongs to the executive branch so he has different tasks and the constitutionality of laws is checked by the judicial branch.