Psychologists are likely to doubt that chimpanzees can use complex grammar, despite their abilities in communication and cultural transmission. They can convey messages using gestures and form basic concepts, but their grasp of the complexities of language is limited. Thus, the chosen answer is C.
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Psychologists are likely to doubt that chimpanzees can use complex grammar, despite their abilities to communicate and transmit cultural knowledge. While they show intelligence, their grasp of intricate grammatical structures is limited. Thus, the answer is option C. ;