(A) Kieselguhr (Diatomaceous earth)
⟶ Used for filtration (it is a fine, porous, siliceous material).
- So,
(A)⟶( III
) Filtration plants
(B) Silica gel
⟶ Used in chromatography as an adsorbent.
So,
(B)⟶(I) Chromatographic material
(C) ZSM-5 (a type of zeolite catalyst)
⟶ Used to convert alcohol directly into gasoline (in petrochemical industry).
So, (C)
⟶ (IV) To convert alcohol directly into gasoline
(D) Hydrated zeolites
⟶ Used in softening of hard water (by ion exchange).
- So, (D)
⟶ (II) Softening of hard water
Now, putting it all together:
(A)-III, (B)-I, (C)-IV, (D)-II
Correct Answer: Option D