Which of these keywords is used by a class to use an interface defined previously?Select one:ImplementimplementsImportsimport

The correct keyword used by a class to implement an interface defined previously is implements.

Explanation

1. Understanding Interfaces: In Java, an interface is a reference type, similar to a class, that can contain only constants, method signatures, default methods, static methods, and nested types. It cannot contain instance fields.

2. The 'implements' Keyword: When a class wants to use an interface, it must declare that it implements that interface using the keyword implements. This means that the class must provide concrete implementations for all the methods defined in the interface.

3. Other Keywords:

   • Import: This keyword is used to bring other classes, interfaces, or packages into visibility in your source code, but it does not establish a relationship like implementing an interface.
   • Implement / Import: These are not valid keywords in Java for the purpose of using interfaces.

Conclusion

Thus, when a class implements an interface in Java, it uses the keyword implements to signify that the class is providing concrete methods for the abstract methods declared in the interface.