Which polymer has 'chiral' monomer(s) ?

Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm) :

Among the statements (a)-(d) the correct ones are :

(a) Lithium has the highest hydration enthalpy among the alkali metals.

(b) Lithium chloride is insoluble in pyridine.

(c) Lithium cannot form ethynide upon its reaction with ethyne.

(d) Both lithium and magnesium react slowly with H₂O.

The correct order of the spin-only magnetic moments of the following complexes is :
(I) [Cr(H₂O)₆]Br₂
(II) Na₄[Fe(CN)₆]
(III) Na₃[Fe(C₂O₄)₃] ($$\Delta $$₀ $$>$$ P)
(IV) (Et₄N)₂[CoCl₄]