Final answer:
Singing nursery rhymes is the activity that addresses the conversation component for a three-year-old.
Step-by-step explanation:
The activity that addresses the conversation component for a three-year-old is singing nursery rhymes. At this age, toddlers are able to speak in short sentences and ask questions. Singing nursery rhymes helps to develop their language skills, improve their vocabulary, and encourage social interaction. It also introduces them to the rhythm and patterns of language, which is essential for conversation.