Which statement most accurately describes a limitation of UV disinfection?

Which statement most accurately describes a limitation of UV disinfection?

• A. It is effective only at high turbidity.
• B. It produces residual disinfectant in the effluent.
• C. It requires chemical dosing to work.
• D. It requires clear water with sufficient UV transmittance; turbidity or color reduces effectiveness and may require pretreatment.

Answer: (D)