B is the correct answer.
In Marbury v. Madison, Chief Justice Marshall developed a doctrine that is commonly known as Judicial Review.
Judicial Review gives the Supreme Court the right/obligation/duty to hear cases about the actions of the executive or legislative branch and to make a determination about the constitutionality of the executive or legislative branches' actions
Answer: It showed that progress was being made in defeating the South, and it helped persuade Union voters to re-elect Lincoln as President.