A. It uses a capacitor to improve running efficiency.

B. The auxiliary winding remains connected during normal operation.

C. It produces high starting torque due to the capacitor’s phase-shifting effect.

D. A low-value capacitor is used for continuous operation.

Answer: 

C. It produces high starting torque due to the capacitor’s phase-shifting effect.

Explanation: The capacitor creates a phase difference between the main and auxiliary winding currents, generating a strong rotating magnetic field for high starting torque. The auxiliary winding is disconnected after starting (ruling out B), and the capacitor is not used for running efficiency (ruling out A and D).