Match the enteries of column I with appropriate entries of column II Each entry in column I may have one or more than one correct option from column II .
`{:(,"Column I ","Column II "),((A),"C1 ,Br, I",(p) "Ionization enthalpy increases "),((B) ,"B,C,O ",(q) "Negative elecron gain enthalpy decreases "),(( C ) ,O^(2-) "," O^(-) "," O^(-) ", "O,(r ) " Atomic size decreases "),(( D ),"C1 ,F ,P" ,( s) "Belong to the same group "):}`

Explanation

To match the entries of Column I with the appropriate entries of Column II, we will analyze each entry in Column I and determine which options from Column II are correct based on the properties of the elements involved.

### Step-by-Step Solution:

1. **Entry A: Cl, Br, I**
- These elements belong to Group 17 (halogens).
- **Match with (s)**: "Belong to the same group" is correct because Cl, Br, and I are all halogens.
- **Match with (q)**: "Negative electron gain enthalpy decreases" is also correct. As you move down the group, the ability to gain electrons decreases due to increasing atomic size.
- **No match with (p)**: "Ionization enthalpy increases" is incorrect because ionization enthalpy decreases down the group.

**Matches for A: (s), (q)**

2. **Entry B: B, C, O**
- These elements are in the same period (2nd period).
- **Match with (r)**: "Atomic size decreases" is correct because atomic size decreases across a period.
- **No match with (s)**: They do not belong to the same group.
- **No match with (p)**: "Ionization enthalpy increases" is correct, but the statement is about decreasing, so it is incorrect.
- **No match with (q)**: "Negative electron gain enthalpy decreases" is incorrect; electron gain enthalpy actually increases across the period.

**Matches for B: (r)**

3. **Entry C: O^(2-), O^(-), O**
- These are isoelectronic species.
- **Match with (r)**: "Atomic size decreases" is correct. The more negative charge an ion has, the larger it is, so O^(2-) is larger than O^(-), which is larger than O.
- **No match with (s)**: They do not belong to the same group.
- **No match with (p)**: "Ionization enthalpy increases" is incorrect; it actually decreases as you go from O to O^(-) to O^(2-).
- **Match with (q)**: "Negative electron gain enthalpy decreases" is correct because the tendency to gain electrons decreases as the negative charge increases.

**Matches for C: (r), (q)**

4. **Entry D: Cl, F, P**
- Cl and F are halogens, while P is a non-metal in Group 15.
- **Match with (s)**: "Belong to the same group" is incorrect; Cl and F are in Group 17, but P is in Group 15.
- **No match with (r)**: Atomic size does not follow a consistent trend among these three.
- **Match with (q)**: "Negative electron gain enthalpy decreases" is correct. Cl has a higher electron gain enthalpy than P.
- **No match with (p)**: "Ionization enthalpy increases" is incorrect; Cl has a higher ionization enthalpy than P.

**Matches for D: (q)**

### Final Matches:
- **A:** (s), (q)
- **B:** (r)
- **C:** (r), (q)
- **D:** (q)