What is a letter or letter combination that represents a single phoneme?

The correct answer is 'grapheme.' A grapheme is defined as the smallest unit in a written language that represents a sound, or phoneme. This can be a single letter, like 'b' or 'c,' or a combination of letters that together represent one sound, such as 'sh' in 'ship' or 'ch' in 'chair.'

Graphemes are essential in the study of phonics and spelling as they connect sounds (phonemes) to their written forms. Understanding graphemes helps learners decode and spell words correctly, as they learn how different letters and combinations of letters correlate to specific sounds.

This contrasts with the other terms mentioned. A digraph consists of two letters that represent one sound, hence it is a specific type of grapheme. A blend refers to two or more consonant sounds that are pronounced together yet retain their own sounds, like 'st' in 'stop.' Lastly, a phoneme is the smallest unit of sound in speech rather than a written representation. Understanding these distinctions is critical in foundational reading skills.