Emisor - Means : Sender
Mensaje - Means : Message
Canal - Means : Channel
Receptor - Means : Receiver
Contexto - Means : Context
Codigo - Means : Code
Enuciado - Means : Enuciado ??? Is that what u want.. I hope or i just sent u a COMPLETELY Offtopic message.
The answer is nunca which means never and nadie means nobody and nada is nothing so the final answer is:
Nunca
Answer
the second one goes to the third one and the third one to the second