By about 15 months, what language milestone is typical?

• A. Vocabulary of about 4–6 words and using them functionally
• B. Vocabulary of 10–20 words
• C. Uses 2-word phrases
• D. Speaks in full sentences

Answer: (A)

The main idea is that expressive language is still in early stages at about 15 months. By this age, many children have a small spoken vocabulary—roughly 4–6 words—and they use those words purposefully to label familiar people or objects, request something, or get attention. They often understand more than they say and rely on gestures alongside spoken words.

Saying 10–20 words tends to appear a bit later, around 18–24 months, and using 2‑word phrases typically follows around the second year as word combinations begin. Speaking in full sentences develops much later, usually several years down the line. So a 4–6 word vocabulary used functionally is the best fit for about 15 months.