- (A) $$\text{NH}_4\text{Cl} + \text{NH}_4\text{OH}$$: Group III precipitating reagent, which selectively precipitates $$\text{Al}^{3+}$$ as its hydroxide.
$$\implies \text{(A)} \rightarrow \text{(III)}$$
- (B) $$\text{NH}_4\text{OH} + \text{Na}_2\text{CO}_3$$: Group V precipitating reagent (or alternative Group V carbonating mixture), which precipitates $$\text{Sr}^{2+}$$ as its carbonate.
$$\implies \text{(B)} \rightarrow \text{(IV)}$$
- (C) $$\text{NH}_4\text{OH} + \text{NH}_4\text{Cl} + \text{H}_2\text{S}\text{ gas}$$: Group IV precipitating reagent, which precipitates $$\text{Mn}^{2+}$$ as its sulfide.
$$\implies \text{(C)} \rightarrow \text{(I)}$$
- (D) Dilute $$\text{HCl}$$: Group I precipitating reagent, which precipitates $$\text{Pb}^{2+}$$ as its chloride.
$$\implies \text{(D)} \rightarrow \text{(II)}$$
Conclusion:
Aligning the systematic inorganic qualitative group separation reagents leads to the correct matching pattern.
Answer: Option A — A-III, B-IV, C-I, D-II