To make a circuit, you need at least a power source (like a battery) and a conductor to allow the current to flow. Therefore, the sufficient option to make a circuit would be:
C. conductor and battery
The conductor allows the electrical current to flow, while the battery provides the necessary electrical energy. The insulator (option B and D) would not be useful for making a circuit as it does not allow current to flow. Option E (just a battery) is also insufficient because you need a conductor to complete the circuit.