The argument that favors federal judges having lifetime appointments is that the judges can rule on cases without fearing retribution.
The Federal court have a justice system which is headed by Federal judge which are nominated and approved by the President and Senate respectively.
In United states, once a judge is been approved as a federal judge, the appointment of the judge is for lifetime.
The primary reason for the lifetime appointment is to insulate them from external pressures especially from the executives.
Therefore, Option D is correct because the lifetime appointment will allow them can rule on cases without fearing retribution from the executives.
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