Which salesforce community licenses require a role associated with an account? (Choose two answers)

Answer options:

A.Customer Community Plus
B.Partner Community
C.Lightning External Apps
D.Customer Community

Correct Answer: A and B 
Customer community plus licenses and partner community require a role associated with an account. 
Options C and D are incorrect because this type of licenses doesn’t require a role. 
Reference:

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