The Naming Explosion Typically Occurs at 18 Months,but the Timing

The naming explosion typically occurs at 18 months,but the timing of this event varies widely for individual children.Which of the following is NOT correct regarding individual differences in word learning?

A) Twin studies find that vocabulary size is more similar in identical twins than in fraternal twins indicating a role for genetics.
B) Children have larger vocabularies when they are exposed to high-quality language.
C) Children who have difficulty remembering speech sounds accurately find word learning particularly challenging.
D) Children learn fewer words when their parents' speech is rich in different words and is grammatically sophisticated.