Which of the following components is essential for lowering iron losses in transformers?

Lowering iron losses in transformers is crucial for improving efficiency and reducing energy waste. Iron losses primarily consist of hysteresis and eddy current losses. Eddy current inhibitors are specifically designed to reduce eddy current losses, which occur due to the circulating currents induced within the core when it is subjected to alternating magnetic fields.

By incorporating eddy current inhibitors, such as laminated cores or using materials with high electrical resistivity, the flow of these currents can be minimized. This results in lower energy dissipation in the form of heat, ultimately leading to improved efficiency in the transformer.

The other options do not directly address the specific issue of iron losses. Insulation pertains to preventing current leakage and ensuring safety. The conductor size affects the resistance and overall efficiency but is not specifically related to the iron losses in the transformer's core. High-frequency operation can actually increase losses due to hysteresis and other factors, rather than reduce them. Therefore, eddy current inhibitors stand out as the key component for effectively reducing iron losses in transformers.