Find an Equation in Spherical Coordinates for the Equation Given $y = 4$

Multiple Choice

Find an equation in spherical coordinates for the equation given in rectangular coordinates. $y = 4$

A) $\beta = 4 \cos \phi \cos \theta$
B) $\beta = 4 \sec \phi \sec \theta$
C) $\rho = 4 \sin \phi \sin \theta$
D) $\rho = 4 \sec \phi \csc \theta$
E) $\beta = 4 \csc \phi \csc \theta$