People usually access social networking sites to be informed and entertained, as well as to connect to others and:
o a. outline their thoughts.
o b. earn better grades.
o c contribute or create something.
o d. buy digital media.

A. outline their thoughts.  

Explanation:

Social networks are used to inform, entertain, connect with others, and outline your thoughts. This is because the interaction that social networks provide, lets the people form their opinions, delineating their thoughts about something, through some information they see, or the comment that a friend made, or the photo that was posted.

the answer is d. amendments.

citizens were able to charge more for their goods and services