Which of the following is the correct way to call the subroutine function abc() of the given class csharp given below?

• A. csharp c = new csharp();delegate void d = new del(ref abc);d();
• B. delegate void del();del d;csharp s = new csharp();d = new del(ref s.abc);d();
• C. csharp s = new csharp();delegate void del = new delegate(ref abc);del();
• D. None of the mentioned