You are configuring SharePoint 2013 social features.
You need to ensure that users receive email notifications that relate to their microblogging activities.
Which settings should you configure from the User Profile Service Application? (To answer, select the
appropriate link in the answer area.)
Hot Area:
Answer: 
Explanation:
Enable microblogging e-mail notifications: On the Setup My Sites page, under E-mail Notifications, select
Enable newsfeed email notifications if you want users to receive email notifications that relate to theirmicroblogging activities.
What’s new in social computing in SharePoint Server 2013
https://technet.microsoft.com/en-us/library/jj219766.aspx