Give an example of an abstract class implementation.?

Short answer: abstract class Employee {

Example code

public string Name { get; set; }
public abstract void Work();
public void Report() => Console.WriteLine("Reporting work done"); }
class Developer : Employee
{
public override void Work() => Console.WriteLine("Writing code"); }
class Tester : Employee
{
public override void Work() => Console.WriteLine("Testing application"); } // Usage Employee dev = new Developer() { Name = "Alice" }; dev.Work(); dev.Report();

Real-world example (ShopNest)

Checkout calls IPaymentGateway.Charge(). Razorpay and Stripe adapters implement the same interface, so ShopNest can switch gateways without rewriting the order service.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.