Polarization as a function of the viewing angle Θ for five different viewing angles: Θ = 180° ,135° ,90° ,45°  and 0°. In each different colored curve, we remove the contribution of photons that scattered less times than what is written in the legend. Top panel: Simulation s2 from Fig. 4. Removing photons that scatter 10 or less times minimally affects the result. The polarization level is dominated by the multiple-scattered photons. Bottom panel: Same as top panel but for the simulation s3 of Fig. 5. In the lower density regime of Case B, the polarization is dominated by emerging photons that experienced ≲5 scatterings. The positive q values around the viewing angles of Θ = 135° are set by photons that scattered only once.