The correct answer is A. Air motor.
Air motors are preferred for use in mines where explosive gases exist because they do not produce sparks. Spark-producing motors, such as induction motors, can ignite explosive gases, causing a fire or explosion. Air motors are also less likely to cause arcing, which can also ignite explosive gases.
Induction motors are the most common type of motor used in industry. They are simple, reliable, and efficient. However, they can produce sparks, which can ignite explosive gases.
Shunt motors are a type of DC motor. They are more efficient than induction motors, but they can also produce sparks.
Synchronous motors are a type of AC motor. They are very efficient, but they can also produce sparks.
Air motors are powered by compressed air. They are simple, reliable, and efficient. They do not produce sparks or arcing, so they are safe to use in mines where explosive gases exist.