White phosphorus on reaction with lime water gives calcium salt of an acid `(A)` along with a gas `(X)`. Which of the following is correct ?

Explanation

To solve the problem, we need to analyze the reaction of white phosphorus with lime water and identify the products formed, including the calcium salt of an acid and the gas released.

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this case are white phosphorus (P4) and lime water (calcium hydroxide, Ca(OH)2).

2. **Write the Reaction**:
- The reaction can be represented as:
\[ P_4 + Ca(OH)_2 \rightarrow CaH_2PO_2 + PH_3 \]
- Here, calcium hypophosphite (CaH2PO2) is formed along with phosphine (PH3) gas.

3. **Identify the Acid (A)**:
- The calcium salt formed is calcium hypophosphite, which corresponds to the acid H3PO2 (hypophosphorous acid). Thus, the acid (A) is H3PO2.

4. **Identify the Gas (X)**:
- The gas released in the reaction is phosphine (PH3), which we denote as gas (X).

5. **Analyze the Statements**:
- **Statement 1**: "A on heating gives X and O2".
- When H3PO2 is heated, it decomposes to form PH3 and H3PO4. However, it does not produce O2. Thus, this statement is incorrect.
- **Statement 2**: "A is a dibasic acid".
- H3PO2 is a monobasic acid because it has only one replaceable hydrogen ion. Therefore, this statement is also incorrect.

6. **Conclusion**:
- Since both statements are incorrect, the correct answer is that none of the provided statements are correct.

### Final Answer:
None of the statements are correct.