How are the number of cycles per second developed by the alternator aboard your vessel determined?

Correct Answer: Option A — the speed of the engine driving the alternator

The output frequency in hertz of a marine alternator is determined by the formula $f = (P \times N) / 120$, where $P$ is pole count and $N$ is prime mover speed. Because pole count is fixed, frequency is directly controlled by the prime mover's operating RPM.