Q: 75 (CAPF/2011)

What is the correct sequence for treatment of polluted surface water ?
1. Disinfection and fluoridation
2. Screening and mixing
3. Flocculation and sedimentation
4. Filtration and sludge processing
Select the correct answer using the code given below :
question_subject: 
Science
question_year: 
2011
question_exam: 
CAPF
stats: 
0,856,1448,368,736,856,344