Which of the following is NOT a standard size for circuit breakers?

The correct answer is that 75 Amps is not a standard size for circuit breakers commonly found in residential and light commercial applications. Circuit breakers are usually available in a range of standard amperage ratings for typical loads, with 15 Amps, 20 Amps, and 30 Amps being widely used for branch circuits.

In residential settings, 15 and 20 Amp breakers are standard for outlets and lighting circuits. A 30 Amp breaker is often used for larger appliances, such as dryers or water heaters. However, while higher amperages like 75 Amps do exist, they are not standard for typical circuit-breaking applications; such sizes are more commonly found in specialized industrial or commercial equipment. Therefore, 75 Amps does not fit within the standard sizing used in most typical installations.