Which of the following pairs are correctly matched?
1. Lime soda process \(\leftrightarrow\) Softening
2. Nalgonda technique \(\leftrightarrow\) Fluoride removal.
3. Aeration \(\leftrightarrow\) Coagulation
4. Ozonation \(\leftrightarrow\) Disinfection.
Select the correct answer using the codes given below: Codes:
1
1, 2 and 3
2
1, 3 and 4
3
1, 2 and 4
4
2, 3 and 4
5
Question Not Attempted