Which of the following function with the same identifer can NOT be compiled together with the code above?

Question 3 Suppose we have a function already defined as following int func(int x) { // do somthing on x return x; } Which of the following function with the same identifer can NOT be compiled together with the code above? This is correct? int func(int &x) { return x; } Likely to be this? int func(int **) { return **; > How about this? int func(double x) { return x; > Maybe this one? double func(int x){ return x; } Probably this is problematic? enum color { kRed, kGreen, kBlue }; int func(color x) { return x; }