What sound does the letter 'ɛ' represent?

The letter 'ɛ' represents the "eh" sound, which is a mid-front, lax vowel commonly found in English words such as "bed," "red," and "said." This sound is produced with the tongue positioned slightly below the mid-line in the mouth and the lips in a neutral position, resulting in the characteristic quality associated with the "eh" sound.

In contrast, the other options describe different vowel sounds, with "ih" typically denoting a high front lax vowel as heard in "bit," "eee" representing a high front tense vowel as in "see," and "Ah" referring to an open back vowel often represented by 'a' as heard in "father." Each of these sounds has distinct articulatory qualities that differentiate them from the "eh" sound represented by 'ɛ.'