"effective speakers must be aware of their nonverbal messages. nonverbal means
a. content delivered by visual aids.
b. information included on the outline, but not in the speech.
c. appearance, movements, and vocal qualities.
d. body language only."

c. appearance, movements, and vocal qualities.

Explanation:

Nonverbal communication is a means of communication by which a message is conveyed by using visual, auditory, tactile, and kinesthetic (physical) channels.

Types of non verbal communication

Kinesics

This refers to the movement of the body which communicating. For example, hand gestures.

Haptics

This refers to the message conveyed by touch. For example, pat on the back.

Paralanguage

This refers to the message being conveyed with the use of different vocal qualities. For example, the pitch, speed of speech.

Proxemics

This refers to the message which is conveyed by the proxmity of the receiver and the sender. For example, being close to someone might intimidate the other person.

Chronemics

This refers to the influence of time on communication. For example, in cultures that are diurnal will not prefer a meeting at night.