Research has shown that a. direct stimulation of language development is discouraged in some cultures. b. genetics plays very little role in verbal ability. c. language development in American...

Research has shown that

a. direct stimulation of language development is discouraged in some cultures.

b. genetics plays very little role in verbal ability.

c. language development in American children is not linked to income-level of parents.

d. maternal responsiveness to American children’s vocalizations had no impact on when children reached language milestones