Which one is NOT Lambda expression?

165.

MyDel del = (int x) => { return x + 1; } ;

MyDel del = (x) => { return x + 1; } ;

MyDel del = x => { return x + 1; } ;

MyDel del = x => x + 1 ;

MyDel del = delegate(int x) { return x + 1; } ;

All lambda expressions use the lambda operator =>, which is read as "goes to". The left side of the lambda operator specifies the input parameters (if any) and the right side holds the expression or statement block. The lambda expression x => x * x is read "x goes to x times x."