Judicial review is the power of the US Supreme Court to A-impeach a sitting president. B-work with state supreme courts. C-declare laws as unconstitutional. D-veto legislation from Congress.

C. declare law as unconstitutional

Judicial review is the main power of the US Supreme Court. The Supreme Court case of Marbury v. Madison was what established that the Supreme Court had the power to determine whether a law was constitutional or not, that is what judicial review is.