To answer this question, we need to understand the concept of multilevel inheritance.
Multilevel inheritance occurs when a class inherits from another class, which in turn inherits from another class.
Let's go through each option to determine which one represents multilevel inheritance:
Option A) class A, class B extends A, class C extends B - This option represents multilevel inheritance because class B extends class A, and class C extends class B.
Option B) class A implements B, implements C - This option represents multiple interface implementation, not multilevel inheritance. In Java, a class can implement multiple interfaces, but it can only extend one class.
Option C) class A extends B, extends C - This option represents multiple inheritance, not multilevel inheritance. In Java, a class can only extend one class.
Option D) none of the above - This option is incorrect because option A represents multilevel inheritance.
Therefore, the correct answer is option A.