Select the incorrect pair from the following pairs of treatment unit and impurities removed, in waste water treatment system:
a) Grit chamber - Sand, silt
b) Aeration tank - Suspended impurities
c) Skimming tank - Fat and Grease
d) Screen - Cloth, paper
1
(b) and (c)
2
(a) and (c)
3
Only (c)
4
Only (b)