enumeralbe_arg_rec.cs

public class SuperDTO 
{ 
    public string A {get; set; } 
    public string B {get; set; } 
    public string C {get; set; } 
    public int D {get; set; } 
}

public class A{
   public void M1(SuperDTO[] inp){}

   public class M2Arg 
   {
    public string A {get; set; }
    public string B {get; set; } 
    public string C {get; set; } 
    public int D {get; set; } 
   }
   public void M2(M2Arg[] inp){}

   public void M3(Tuple<string, string, string, int>[] inp){}
}