Which statement about abstract methods is true?

Which statement about abstract methods is true?

• A. They must have a body
• B. They can be static
• C. They are declared with the abstract keyword and have no body
• D. They cannot be declared in interfaces

Answer: (C)

Abstract methods define a contract for subclasses by declaring the method signature without providing an implementation. They must be declared with the abstract keyword and do not include a body; the declaration ends with a semicolon, and the concrete behavior is supplied by each subclass through overriding. This is why that statement is the accurate one: it captures the essential form and purpose of abstract methods. The other ideas don’t fit: an abstract method cannot have a body, so requiring a body is wrong; making a method static would mean it belongs to the class rather than an instance and cannot be overridden to provide a concrete implementation; and while interfaces relate to abstract behavior, their methods are abstract by default in many languages (with some modern exceptions like default methods that do have bodies), so the plain notion of an abstract method being declared with no body is the clean, central rule.

Abstract methods define a contract for subclasses by declaring the method signature without providing an implementation. They must be declared with the abstract keyword and do not include a body; the declaration ends with a semicolon, and the concrete behavior is supplied by each subclass through overriding.

This is why that statement is the accurate one: it captures the essential form and purpose of abstract methods. The other ideas don’t fit: an abstract method cannot have a body, so requiring a body is wrong; making a method static would mean it belongs to the class rather than an instance and cannot be overridden to provide a concrete implementation; and while interfaces relate to abstract behavior, their methods are abstract by default in many languages (with some modern exceptions like default methods that do have bodies), so the plain notion of an abstract method being declared with no body is the clean, central rule.