What is the purpose of a "low-pass filter"?

A) To allow only high frequencies to pass

B) To block all frequencies above a certain cutoff

C) To amplify all frequencies equally

D) To remove noise from a signal

Answer: B) To block all frequencies above a certain cutoff

Explanation: A low-pass filter allows signals with frequencies lower than a specified cutoff frequency to pass through while attenuating frequencies higher than the cutoff, commonly used to remove high-frequency noise.