What is referred to as the receiver's response to a message?

The term that describes the receiver's response to a message is feedback. Feedback is a crucial part of the communication process; it allows the sender to understand how their message was interpreted, which can influence future communication. This response can take many forms, such as verbal comments, non-verbal cues, or actions, and is essential for clarifying understanding and improving communication effectiveness.

Other concepts in the question also relate to communication but differ in meaning. Interference, for instance, refers to anything that disrupts the transmission or reception of the message and can hinder effective communication rather than enhance it. Content pertains to the actual information or meaning conveyed in the message itself, while purpose relates to the objective or intention behind sending the message. Understanding that feedback is a response helps reinforce the importance of interaction in communication, which is particularly valuable in dynamic environments such as fire and emergency services.