Color distribution of the galaxies within the sky-localization area (N₁₀₀, green), galaxies within the galaxies within the sky-localization area contribution to the 90% probability of being the true host (N₉₀, blue) and the true host (Host, red). Upper panel: Cumulative distribution function (CDF) of the u  −  g, g  −  r, r  −  i and i  −  z colors for N₁₀₀, N₉₀ and true host. The horizontal black line corresponds to the value where the CDF of the Host reaches 10%. Lower panels: Probability distribution function (PDF) of the u  −  g, g  −  r, r  −  i and i  −  z colors for the three samples studied. In all the plots, the distributions correspond to the galaxies associated with CGWs whose S/N > 25.