The disinfection efficiency of chlorine increases by_______________?_x005F_x000D_1) decreasing the time of contact_x005F_x000D_2) decreasing the temperature of water_x005F_x000D_3) increasing the temperature of water_x005F_x000D_The correct answer is ?

• A. only (1)
• B. both (1) and (2)
• C. both (1) and (3)
• D. only (3)