Which of the following best describes a phoneme?

A phoneme is the smallest unit of sound in a language that can distinguish one word from another. For example, the difference between the words "bat" and "pat" lies in the initial phonemes /b/ and /p/, which create a difference in meaning. Recognizing phonemes is crucial in developing phonemic awareness, contributing significantly to reading and language development because it helps learners understand how sounds combine to form words.

When discussing the other definitions, a small unit of meaning in words relates to morphemes, which are the smallest units of meaning rather than sound. A complex sound pattern refers to combinations of phonemes or syllables, but does not define a single phoneme. Lastly, a type of vowel sound does not encompass the entire category of phonemes, as phonemes include both consonants and vowels. Thus, the choice that accurately describes a phoneme is that it is the smallest unit of speech distinguishing words.