What is the main function of a digital comb filter?

A) To amplify signals

B) To remove specific frequencies

C) To create a series of notches in the frequency response

D) To provide a uniform gain across all frequencies

Answer: C) To create a series of notches in the frequency response

Explanation: A digital comb filter introduces a series of notches in the frequency response, effectively attenuating specific frequencies while allowing others to pass, useful for applications like echo cancellation.