Final answer:
The receiver in the communication process option b. decodes the symbols to understand the message. Decoding involves translating sender-encoded symbols back into ideas. Recognizing and decoding a message from an alien species would be significantly more complex due to likely unfamiliar forms and lack of a shared basis for understanding.
Step-by-step explanation:
During the communication process, the receiver's role is to decode the symbols to interpret the meaning of the message. This involves taking the symbols, words, or gestures that the sender has encoded and translating them back into thoughts or ideas that they can understand. Understanding a message involves recognition of the symbols used and connecting them to the intended meaning as conveyed by the sender. While encoding is the process of creating the message, decoding is focused on the interpretation.
In broader contexts, such as when considering messages from an alien species, the challenge becomes significantly more complex. Deciphering such a message would depend on recognizing it as a message in the first place and then having some basis for translating the symbols or signals into something meaningful. There might be no shared basis for understanding, and the message might indeed take a form that is completely unexpected and unfamiliar.