MCQ Practice Question Signals & SystemsDiscrete-Time LTI Discrete-time convolution uses? AA summation over an integer index BOnly a continuous integral CMatrix inversion always DDifferentiation only Show AnswerHide AnswerReport an error Correct Answer: A. A summation over an integer index Explanation: y[n]=sum x[k]h[n-k].Reference: Standard signals and systems: discrete-time lti