Which of the following statements about nonverbal communication are true?（ ）
选项：

A:In some cultures, people still schedule their day on “event time”, such as after lunch, before sunset etc. According to Dr. Albert Mehrabian, almost 28 percent of meaning in communication is presented from various tones.
C:Such body movements as gestures, postures, eye contact are culturally specific.
D:Nonverbal signals can modify what is said in words but never substitute for words.