What does the term "power spectral density" (PSD) refer to?

A) The total power of the signal

B) The distribution of power across various frequency components

C) The energy of the signal over time

D) The amplitude of the signal

Answer: B) The distribution of power across various frequency components

Explanation: Power spectral density (PSD) describes how the power of a signal is distributed with frequency, providing insights into the signal's frequency characteristics and energy distribution.