A phoneme refers to

A. a mental grouping of words being heard during "inner audition"

B. the shortest segment of speech that, if changed, changes the meaning of the word.

C. the property of combining words into unique sentences.

D. the first word produced by infants, usually during their second year.

B. the shortest segment of speech that, if changed, changes the meaning of the word.

Explanation:

A phoneme is the smallest unit of sound in speech that distinguishes one word from another and it doesn't have a meaning by itself, for example, in the words cat, pat and sat, the letter t is the phoneme element. These sounds usually are used by parents to coax babies to talk.

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