What was the biggest mistake made by confederates that the union gain a victory at shiloh

Me! why was marbury v. madison such an important case? a. it confirmed that the supreme court was more powerful than congress but less powerful than the president b. it confirmed the authority of the supreme court to review a law in to determine whether or not that law is constitutional. c. it confirmed the authority of congress to increase or decrease the power of the supreme court. d. it gave the supreme court the power to confirm federal judges.