What is wrong with the following code?

int f1( int x, int y)
{
x = y * y;
return x;

int f2( float a, float& b)
{
if(a < b)
b = a;
else
a=b;
return 0.0;
}
}

a. Neither function should return a value
b. Function definitions may not be nested
c. Both parameters to f2 should be pass-by reference
d. in f2, a can not be assigned b.
e. nothing is wrong

b. Function definitions may not be nested