What needs to be configured for the SoftPhone to work in Salesforce?

Universal Containers is using the Service Cloud Console for managing cases. They would like to add the Salesforce SoftPhone to enable click-to-dial capability.

What needs to be configured for the SoftPhone to work in Salesforce? Choose 3 answers
A . Assignthe Salesforce users to the Call Center.
B . Install an adapter from AppExchange to work with third-party CTI systems
C . Use Apex to create an adapter to work with third-party CTI systems
D . Create a SoftPhone layout and assign to user profiles
E . Assign the Salesforce CTI license to Salesforce users

Answer: A,B,D