The one having maximum protective power (G.No. = Gold number)
Gelatin (G.No.0.01)
Engg albumin (G.No.015 to 0.25)
Starch (G.No.25)
Gum Arabic (G.No.15)
Lower the gold number, higher its protective power
The gold number of four protective colloids a, b, c and d are 0.1,0.25,5and 15 respectively. the maximum protecting power is of