Which term best defines the acoustic representation of language?

The term that best defines the acoustic representation of language is "speech." Speech refers specifically to the vocalized form of human communication, which encompasses the sounds produced by the human vocal apparatus. It includes the articulation of sounds, changes in pitch and loudness, and various speech patterns, all of which create the acoustic signals that make up spoken language.

In contrast, "communication" is a broader term that encompasses all forms of expressing and receiving information, including non-verbal cues and written forms. It is not limited to the acoustic aspect of language. While "fluency" relates to the smoothness and flow of speech, it does not define the acoustic representation itself. "Articulation," on the other hand, focuses specifically on how speech sounds are produced, rather than representing language as a whole. Therefore, "speech" directly relates to the acoustic nature of language, making it the correct answer.