Which method in an abstract class must be overridden in its subclasses?   Concrete methodsAbstract methodsClass methodsStatic methods

Break Down the Problem

1. Identify the types of methods listed: Concrete methods, abstract methods, class methods, and static methods.
2. Understand the definition of an abstract class and its purpose: An abstract class serves as a template for other classes and cannot be instantiated on its own.

Relevant Concepts

1. Abstract Method: A method defined in an abstract class that does not have an implementation and must be overridden by subclasses.
2. Concrete Method: A method that has an implementation; subclasses inherit these without needing to override them.
3. Class Method: A method that is bound to the class and not the instance; can still be defined in abstract classes but does not require overriding.
4. Static Method: A method that belongs to the class rather than instances; like class methods, it is also not required to be overridden.

Analysis and Detail

• Abstract methods require subclasses to provide a specific implementation, as they lack any operational body within the abstract class.
• Concrete methods allow subclasses to use the provided implementation, and they are not required to override them unless a specific behavior is desired.
• Class methods and static methods can exist in abstract classes but do not enforce a contract for subclasses to provide implementations.

Verify and Summarize

• The only method type that mandates a subclass to provide an overriding implementation is the abstract method.
• Concrete, class, and static methods can either be inherited or optionally overridden, as applicable.

Final Answer

The method in an abstract class that must be overridden in its subclasses is Abstract methods.