The communication process is a two-way interaction between a sender and a receiver.
The sender encodes a message and transmits it through a suitable channel to the receiver.
The receiver then decodes the message to interpret its meaning.
To complete the cycle, the receiver sends a response back to the sender — this response is called feedback.
Feedback confirms whether the message was properly received and understood, helping avoid misunderstandings.
Without feedback, communication remains incomplete and ineffective.
Therefore, the correct answer is Feedback.