A developer created a Lightning Component to display a short text summary for an object and wants to use it with multiple Apex classes.
How should the developer design the Apex classes?

Extend each class from the same base class that has a method getTextSummary() that returns the summary.
Have each class define method getTextSummary() that returns the summary.
Have each class define method getObject() that returns the sObject that is controlled by the Apex class.
Have each class implement an interface that defines method getTextSummary() that returns the summary.

Please let me know which is correct answer form above.