What does "windowing" refer to in signal processing?

A) Applying a mathematical function to a signal

B) Adjusting the amplitude of a signal

C) Filtering out specific frequencies

D) Sampling a signal

Answer: A) Applying a mathematical function to a signal

Explanation: Windowing involves applying a mathematical function (window) to a signal to reduce spectral leakage and improve frequency analysis by limiting the signal's duration in the time domain.