Hiding vs overriding — what does the derived method do in this code? public class Sample { public int x; public virtual void fun() { } } public class DerivedSample : Sample { new public void fun() { } }

Introduction / Context:
In C#, new hides a base member; override replaces it polymorphically. This question distinguishes hiding from overriding.

Given Data / Assumptions:

• Base fun() is virtual.
• Derived fun() uses new, not override.

Concept / Approach:
Using new creates a new member that hides the base member when the variable is typed as DerivedSample. Calls through a Sample reference still bind to the base virtual unless the derived used override.

Step-by-Step Solution:

Why Other Options Are Wrong:

• B: Through a Sample reference, the base virtual dispatch targets the base unless override is used.
• C: Hiding does not replace for all calls.
• D: You can hide without new; the compiler warns but still hides.

Common Pitfalls:
Assuming new implies override-like behavior.

Final Answer:
DerivedSample hides the fun() method of the base class.