Basic phonology and units of speech: Which term names the elementary linguistic units smaller than words that function as the minimal distinctive sounds in a language?

Introduction / Context:
In speech and language processing, it is important to distinguish the basic units that underpin pronunciation and lexical contrast. Understanding these units helps in fields from automatic speech recognition to phonological analysis and language teaching.

Given Data / Assumptions:

• We compare allophones, phonemes, and syllables.
• We seek the elementary units smaller than words that are contrastive in a language.
• The question targets the standard linguistic definition used in phonology.

Concept / Approach:
Phonemes are the smallest units of sound that can distinguish meaning (e.g., /p/ vs. /b/ in English “pat” vs. “bat”). Allophones are context-dependent variants of a phoneme that do not create lexical contrasts (e.g., aspirated [pʰ] vs. unaspirated [p]). Syllables are larger prosodic units typically built from one or more phonemes, not the minimal contrastive units.

Step-by-Step Solution:
Identify the requirement of distinctiveness (meaning-changing power).Map that property to phonemes, not to allophones or syllables.Recognize that syllables are composed of phonemes; they are not minimal units.Select “phonemes.”

Verification / Alternative check:
Minimal-pair tests (e.g., “cap” vs. “cab”) show that swapping one phoneme yields a meaning change; swapping an allophone typically does not change lexical meaning.

Why Other Options Are Wrong:
Allophones: variants of a phoneme; not contrastive.

Syllables: supra-segmental units, larger than phonemes.

All of the above: incorrect because only phonemes satisfy the “elementary, contrastive unit” criterion.

None of the above: incorrect because phonemes fit perfectly.

Common Pitfalls:
Confusing “smaller than a word” with “elementary and contrastive.” Several units are smaller than words, but only phonemes are the minimal contrastive sound units in standard phonology.

Final Answer:
phonemes