Answer:
c. By electing the President and US Congress who make the appointment and approval
Step-by-step explanation:
The nomination of Supreme Court justices is a responsibility of the President of the United States, who proposes his candidates for the job and then the US Congress approves it or not, to this effect the only influence that american public has on the election or not of a certain supreme court justice is the fact that they vote for president and elect congressmen, but other than that, they can't do much