Concept:Redox reactions involve electron transfer and form the basis of electrochemical cells like batteries.Explanation:A dry cell converts chemical energy into electrical energy through redox reactions.A car battery, also called a lead-acid accumulator, operates on redox reactions during both discharging and charging.An electric generator works by electromagnetic induction, not by any redox reaction.So, only the dry cell and the car battery function on redox reactions.Answer:C. I and II only