[单选题]

The main purpose of the text is to tell parents ___________.
A． how to get along with a teenager
B． how to respect a teenager
C． how to understand a teenager
D． how to help a teenager grow up

The main purpose of the text is to tell parents ___________.A． how to get along with a teenagerB． how to respect a teenagerC． how to understand a teenagerD． how to help a teenager grow up