Answer:
C.
Explanation:
A Federal Judge is a judge who can serve in a district court, U. S. Supreme Court, court of appeals, U. S. Court of international trade, etc. These judges are appointed by the President and voted in Senate.
The Constitution regarding their qualification is mute. It says nothing about when a person can be considered qualified to be a federal judge. The rules that have been mentioned in the Constitution concerning federal judges can be found in Article III which states that these judges are to be appointed for a lifetime.
Thus, the correct answer is option C.