The correct answer is D. Governor.
The Governor of a state appoints the State Election Commissioner. The State Election Commissioner is the chief election officer of the state and is responsible for conducting elections to the state legislature and local bodies. The State Election Commissioner is appointed for a term of six years and is not eligible for reappointment.
The Chief Minister is the head of the state government and is responsible for the day-to-day administration of the state. The Chief Justice is the head of the state judiciary and is responsible for the administration of justice in the state. The President is the head of the state and is the supreme commander of the armed forces.
The Chief Minister, the Chief Justice, and the President do not have the power to appoint the State Election Commissioner. The Governor is the only person who has the power to appoint the State Election Commissioner.