Which of the following is the three most common sizes of capacitors used in the power industry?

In the power industry, capacitors are critical components used for power factor correction, voltage stabilization, and load balancing. The correct answer identifies the most common capacitor sizes used to achieve these functions effectively in various applications.

The sizes 100 KVA, 150 KVA, and 200 KVA are commonly used because they align well with typical loads seen in electrical distribution systems, allowing for effective management of reactive power and efficient operation of electrical systems. Capacitors in these KVA ranges are versatile enough to be deployed in various settings, from industrial plants to commercial buildings, making them crucial for maintaining power quality.

When you look at the other options, you will find that while they may represent valid sizes used in specific scenarios, they don't reflect the standard practices or common usage that you would encounter across a broad spectrum of power applications. For instance, sizes such as 10 KVA and 20 KVA are more applicable in smaller residential settings rather than in the power industry, which typically deals with larger capacities. This makes the identified sizes in the correct answer significantly more relevant for linemen in practical settings.