What is not a concern when using social networks?
a. friending people you haven’t met, but who want to friend you
b. posting a report of extreme weather in your area
c. posting photos of friends without their permission
d. posting about a vacation before you’ve returned home

B.posting a report of extreme weather in your area

Explanation:

Social media is considered very harmful in some cases and beneficial in other cases. You are exposed to the world if you put up information regarding your personal life and that can be misused by hackers for personal benefits.

But if you want to create awareness about something or send a message across nations, it is one of the most effective platforms. Posting photos of extreme weather in your area is the only option that is of no concern.

what are the phrases to choose from?

summer because you get to tan and wear cooler clothes and go to the beach