The image with two different color balls on the positive and negative XYZ axes represents option c: the P subshell.
P subshells have three orbitals, Px, Py, and Pz, which are oriented along the x, y, and z axes, respectively. The two different color balls in the image represent the two different phases of the wavefunctions in the Pz orbital. The Pz orbital extends along the z-axis, with the positive phase on the positive z-axis and the negative phase on the negative z-axis.
S subshells have a single spherical orbital, and D and F subshells have more complex sets of orbitals with different shapes and orientations. Therefore, the image is most indicative of the P subshell with its directional and distinct Px, Py, and Pz orbitals.