Which of the following can chatter only users do in Salesforce?

Answer options:

A.Access Salesforce reports and dashboards
B.View Salesforce accounts and contacts
C.Use the calendar to create and track activities
D.All the above

Correct Answer: D 
Chatter only users can access Salesforce reports and dashboards. They can view accounts and contacts in addition to using the calendar to create and track their activities. 
Reference: 

https://help.salesforce.com/articleView?id=standard_profiles.htm&type=5