Is the key to infants learning to associate sounds with meaning.
a. repetition
b. adult responses
c. hearing their own sounds
d. responses of other infants

What is difference between an epidemic and a pandemic? a) an epidemic is a disease; a pandemic is a treatment.b) an epidemic is restricted to a local region; a pandemic is global.c) an epidemic has low mortality; a pandemic has higher mortality.d) an epidemic is caused by a bacterial infection; a pandemic is caused by a viral infection.