Answer:
Invent a sign language themselves
Step-by-step explanation:
As studied under Cognitive Psychology, Communication is the ability of humans to pass their thoughts and also receive response in form of signals, spoken or written signs, which are understood by the participants of this communication.
These signs are all combined to form language. Cognitive psychology on this premise that language is a natural process that must happen, explain that individuals that find themselves in situations such as the above always find a way to communicate.
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