Which of the following statements is NOT true?

Which of the following statements is NOT true?
A、According to semanticists, a word is a unit of meaning.
B、According to grammarians, a word is a free form that can function in a sentence.
C、In visual terms , a word can be defined as a meaningful group of letters printed or written horizontally across a piece of paper.
D、In terms of spoken language, a word is viewed as a sound or combination of sounds which are made involuntarily with human vocal equipment.
【正确答案】：D
【名师解析】:选项D的描述有误。在语言学中，一个词通常被视为由一系列声音组成，这些声音是有意识地通过人类的发音器官发出的，而不是无意识地。因此，D选项与语言学的标准定义不符。其他选项A、B和C分别反映了语义学家、语法学家和视觉定义对词的理解，都是正确的。