C#.NET — Choose the correct implementation for the interface: interface IMyInterface { double MyFun(Single i); }

Introduction / Context:
Interfaces declare member signatures. Implementations may be provided either implicitly (public members matching the signature) or explicitly (qualified with the interface name). This item asks you to recognize valid C# syntax for explicit interface implementation.

Given Data / Assumptions:

• Interface: double MyFun(Single i).
• Language: C# (not VB).

Concept / Approach:
Explicit interface implementation syntax is: returnType InterfaceName.MemberName(parameters) { ... } and appears within a class that lists the interface after the colon. No access modifier is used on explicit implementations.

Step-by-Step Solution:

Verification / Alternative check:
Compile Option D: succeeds. Attempt A/B/C in a C# project: they fail with syntax errors.

Why Other Options Are Wrong:

• A/B/C borrow from other languages or invent syntax not supported by C#.

Common Pitfalls:
Mixing VB and C# syntax when writing interface implementations; remember explicit implementations omit access modifiers and are qualified by the interface name.

Final Answer:
class MyClass : IMyInterface { double IMyInterface.MyFun(Single i) { / code */ } }