Final answer:
The group of gestures, facial expressions, and postures is known as kinesics, which is a form of body language.
Step-by-step explanation:
The correct match for the group of gestures, facial expressions, and postures is kinesics. Kinesics refers to the body movements and gestures that include facial expressions. It is a form of body language and can be interpreted differently by members of different cultures. The question pertains to nonverbal communication, specifically addressing gestures, expression, and postures as forms of body language used in public speaking. These components of nonverbal communication can significantly enhance or change the message conveyed to an audience. For example, gestural communication might include a thumbs-up to show approval, or a furrowed brow to express concern. In the context of public speaking, it's important to apply conventions of speech delivery, including voice control, physical gestures, and maintaining an effective posture. Awareness of cultural considerations is also crucial because specific gestures and expressions might have different interpretations across cultures, impacting the communication process. For instance, making eye contact could be seen as a sign of confidence and honesty in some cultures, while in others it might be perceived as disrespectful or aggressive. Therefore, gaining an understanding of kinesics and paralanguage, and being mindful of these when addressing an audience or interpreting reactions, can lead to more effective communication.