In a digital communication system’s block diagram,

Solution

The correct answer is Demodulator , because at the receiver side of a digital communication system, the incoming modulated signal must be demodulated to recover the original baseband data before decoding. ●      Channel encoder → used at the transmitter to add redundancy for error detection and correction. ●      Modulator → used at the transmitter to map digital data onto a carrier. ●      Source encoder → used at the transmitter to compress or represent source information efficiently.