Onset is the initial consonant or consonant cluster of a syllable that comes before the vowel sound.

• A. Onset
• B. Coda
• C. Nucleus
• D. Rime

Answer: (A)

In syllable structure, the onset is the first consonant or consonant cluster that comes before the vowel. It can be a single sound like /k/ in “cat” or a cluster like /str/ in “street.” The vowel itself is the nucleus, and anything after the vowel is the coda. The rime combines the nucleus and the coda. So the description given—an initial consonant or cluster before the vowel—fits the onset exactly. If a syllable starts with a vowel, the onset is simply empty (zero onset), which still aligns with the idea of something before the vowel. This helps differentiate from the nucleus (the vowel), the coda (consonants after the vowel), and the rime (nucleus plus coda).