Answer to Question 1
At 2 months, infants begin cooing which consist of vowel-like sounds. At about 6 months, babies begin babbling, which is speech like sound that has no meaning and consists of vowel-consonant combinations. Over the next few months, babbling becomes more elaborate as babies experiment with more complex speech sounds. At about 8 to 11 months, infants' babbling sounds more like real speech because infants stress some syllables and vary the pitch of their speech.
Answer to Question 2
c