Question about spherical polar angles?

A plane can be specified with two lines that lie in the plane. For example, two Cartesian coordinate axes x and y specify the xy-plane. By examining the spherical polar coordinates, find the nodal planes of the function f = sin(Theta)*cos(Theta)*cos(phi) and chose one of the following answers:

a. (zy) and (xy)
b. (zy) and (zx)
c. (zx) and (xy)
d. (xx) and (yy)

Any help or explanation you can give me would be much appreciated!
I posted this question here as opposed to under mathematics because I was asked this question for my first year chemistry course. I believe it has to do with wave functions and atomic orbitals in quantum mechanics.