Final Answer:
The missing word is c. illustrators. Illustrators are body language used to accent or contradict a speaker's displays.
Step-by-step explanation:
In the first paragraph of the explanation, it is essential to provide the definition of the term "illustrators" in the context of body language. Illustrators are gestures or movements that accompany speech and are used to emphasize or complement verbal communication. They can enhance the meaning of words, adding emphasis, clarity, or emotional nuance to the spoken message.
The second paragraph should focus on why "illustrators" is the correct choice among the given options. Emblems (a) are specific gestures with well-known meanings, adaptors (b) are self-touching behaviors often associated with comfort or stress, and regulators (d) are gestures that control or coordinate communication. While these terms are relevant to body language, none directly align with the description of movements used to accent or contradict a speaker's displays. "Illustrators" is the most fitting term as it precisely refers to gestures that accompany speech and contribute to the overall communication.
The final paragraph could provide examples or scenarios to illustrate the use of illustrators in communication. This might include instances where hand movements, facial expressions, or other gestures accentuate or contradict the spoken words. Exploring real-world applications reinforces the understanding of why "illustrators" is the most appropriate term for the context provided in the question.