Which linguistic unit is exemplified by the sequence /k/ /ɔ:/ /t/ in the word 'caught'?

• A. Phoneme
• B. Lexical item
• C. Lexical set
• D. Morpheme

Answer: (A)

The sequence shows the basic units of sound that make up the spoken form of a word. Each symbol represents a distinct phoneme—the abstract sound category that can change meaning when its value is altered. In the word “caught,” the three phonemes are the initial /k/, the vowel /ɔ:/, and the final /t; together they form the pronunciation that listeners recognize as that word. Phonemes are about sound structure, not meaning, so this sequence illustrates the phonemic representation of the word.

A lexical item refers to the word as a unit of meaning, not its sound sequence. A morpheme is the smallest meaningful unit, which doesn’t capture the idea of the three distinct sounds in this word. A lexical set groups words by shared vowel sounds, not by the sequence of sounds in a single word. So the best fit for the given sequence is phonemes.