Question 1: Which of the following statements about energy conversion system is true?(single-choice, 10 points) (a) The traditional power system is a centralized bidirectional system. (b) In the Turbine-Generator-Excitor system, the function of excitor is to convert chemical energy or hydro energy to mechanical energy in order to drive generators. (c) The function of transformers is to increase or decrease the voltage, which correspondingly results in the decrease or increase of the current. (d) WestPenn Power is a regional transmission organization (RTO) that coordinates themovement of wholesale in the state of Pennsylvania.