Which of the following cables is larger?

The correct answer is based on understanding American Wire Gauge (AWG) sizing, where a larger number indicates a smaller wire diameter. In this context, the size 3/0 (pronounced "three aught") represents a larger conductor than both 2/0 (two aught) and 1/0 (one aught).

In AWG sizing, as the numbers decrease, the physical size of the wire increases. Therefore, 3/0 is larger than 2/0, 1/0, and 4/0. Among the options, 3/0 has the largest conductor size, making it the suitable choice as the largest cable listed in the question. 4/0, on the other hand, is actually larger than 3/0, but it was not the selected answer. Understanding these wire sizes is crucial for professionals in fields like electrical work and lightning protection, as using the correct wire size ensures effective conductivity and safety in installations.