Match the List -I (containing anions ) with List -II (containing reagent used in testing ) using the codes as given below in the column.
`{:("List"-I,,"List"-II),(("anions"),,("reagents")),((a)S^(2-),,(p)"Barium chloride solution in presence of HCl"),((b)NO_(3)^(-),,(q)"Sodium nitroprusside"),((c)I^(-),,(r)"chlorine water and chloroform"),((d)SO_(4)^(2-),,(s)"iron"(II)"sulphate solution and conc."H_(2)SOS_(4)):}`
Code `:`

Options

A. `{:(,"(a)","(b)","(c)","(d)"),(,"(q)","(s)","(r)","(p)"):}`
B. `{:(,"(a)","(b)","(c)","(d)"),(,"(p)","(s)","(r)","(q)"):}`
C. `{:(,"(a)","(b)","(c)","(d)"),(,"(q)","(p)","(r)","(s)"):}`
D. `{:(,"(a)","(b)","(c)","(d)"),(,"(p)","(q)","(r)","(s)"):}`

Explanation

To match the anions from List-I with the appropriate reagents from List-II, we will analyze each anion and determine the correct testing reagent based on the information provided.

### Step-by-Step Solution:

1. **Identify the Anion: Sulfide Ion (S²⁻)**
- **Reagent:** Sodium nitroprusside
- **Explanation:** The presence of sulfide ions can be detected by treating the sample with sodium nitroprusside, which forms a violet-colored complex.
- **Match:** (a) S²⁻ → (q) Sodium nitroprusside

2. **Identify the Anion: Nitrate Ion (NO₃⁻)**
- **Reagent:** Iron(II) sulfate solution and concentrated sulfuric acid
- **Explanation:** For nitrate ions, when treated with freshly prepared iron(II) sulfate and concentrated sulfuric acid, a brown ring complex is formed at the junction of the two liquids, indicating the presence of nitrate ions.
- **Match:** (b) NO₃⁻ → (s) Iron(II) sulfate solution and concentrated H₂SO₄

3. **Identify the Anion: Iodide Ion (I⁻)**
- **Reagent:** Chlorine water and chloroform
- **Explanation:** The presence of iodide ions can be detected using chlorine water, which oxidizes iodide ions to iodine (I₂). The iodine dissolves in chloroform, forming a violet layer.
- **Match:** (c) I⁻ → (r) Chlorine water and chloroform

4. **Identify the Anion: Sulfate Ion (SO₄²⁻)**
- **Reagent:** Barium chloride solution in presence of HCl
- **Explanation:** When sulfate ions are treated with barium chloride, a white precipitate of barium sulfate (BaSO₄) is formed, indicating the presence of sulfate ions.
- **Match:** (d) SO₄²⁻ → (p) Barium chloride solution in presence of HCl

### Final Matches:
- (a) S²⁻ → (q) Sodium nitroprusside
- (b) NO₃⁻ → (s) Iron(II) sulfate solution and concentrated H₂SO₄
- (c) I⁻ → (r) Chlorine water and chloroform
- (d) SO₄²⁻ → (p) Barium chloride solution in presence of HCl

### Codes:
- A: q
- B: s
- C: r
- D: p