To reflect the function \( f(x) = (x + 1)^2 \) over the x-axis, we take the original function and multiply it by -1.
So, to find \( g(x) \), we apply the transformation:
\[ g(x) = -f(x) = -((x + 1)^2) \]
Thus, the equation for \( g(x) \) is:
\[ g(x) = -(x + 1)^2 \]
This corresponds to the first response option:
g(x) = −(x + 1)².