`A+H_(2)O to B+HCl`
`B+H_(2)O to C+HCl`
Compound (A), (B) and (C) will be respectively:

Options

A. `PCl_(5),POCl_(3),H_(3)PO_(3)`
B. `PCl_(5),POCl_(3),H_(3)PO_(4)`
C. `SOCl_(2),POCl_(3),H_(3)PO_(3)`
D. `PCl_(3),POCl_(3),H_(3)PO_(4)`

Explanation

To solve the problem, we need to identify the compounds A, B, and C based on the hydrolysis reactions provided:

1. **Identify Compound A**:
The first reaction is \( A + H_2O \rightarrow B + HCl \). A common compound that hydrolyzes to produce HCl is phosphorus pentachloride (PCl5). When PCl5 reacts with water, it hydrolyzes to form phosphorus oxychloride (POCl3) and hydrochloric acid (HCl).

Therefore, we can conclude:
- **A = PCl5**

2. **Identify Compound B**:
From the first reaction, we have established that B is phosphorus oxychloride (POCl3). The next reaction is \( B + H_2O \rightarrow C + HCl \). When POCl3 undergoes hydrolysis, it reacts with water to produce phosphorous acid (H3PO3) and HCl.

Therefore, we can conclude:
- **B = POCl3**

3. **Identify Compound C**:
From the hydrolysis of POCl3, we found that it produces phosphorous acid (H3PO3). Thus, we can conclude:
- **C = H3PO3**

In summary, the compounds A, B, and C are:
- **A = PCl5**
- **B = POCl3**
- **C = H3PO3**

### Final Answer:
- A = PCl5
- B = POCl3
- C = H3PO3