The correct answer is D. Decoding.
Encoding is the process of converting information into a form that can be transmitted. Decoding is the process of converting information from a transmitted form into a form that can be understood.
In the context of the question, encoding would be the process of converting symbols, signs, or pictures into a form that can be transmitted, such as a spoken word, a written word, or a gesture. Decoding would be the process of converting the transmitted form back into symbols, signs, or pictures, such as understanding a spoken word, reading a written word, or interpreting a gesture.
A sender is the person or entity that originates a message. A receiver is the person or entity that receives a message.
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