The compound `A` on treatment with `Na` gives `B`, and with `PCl_(5)` gives `C`. `B` and `C` react together to give di Ethyl ether. `A,B` and `C` are in the order
(a)`C_(2)H_(5)Cl,C_(2)H_(6),C_(2)H_(5)OH`
(b)`C_(2)H_(5)OH,C_(2)H_(5)Cl,C_(2)H_(5)Ona`
(c)`C_(2)H_(5)OH,C_(2)H_(6),C_(2)H_(5)Cl`
(d)`C_(2)H_(5)OH,C_(2)H_(5)Ona,C_(2)H_(5)Cl`

Options

A. `C_(2)H_(5)Cl,C_(2)H_(6),C_(2)H_(5)OH`
B. `C_(2)H_(5)OH,C_(2)H_(5)Cl,C_(2)H_(5)Ona`
C. `C_(2)H_(5)OH,C_(2)H_(6),C_(2)H_(5)Cl`
D. `C_(2)H_(5)OH,C_(2)H_(5)Ona,C_(2)H_(5)Cl`

Explanation

To solve the problem step by step, we need to identify the compounds A, B, and C based on the reactions described.

### Step 1: Identify Compound A
The question states that compound A reacts with sodium (Na) to give compound B. A common reaction of alcohols with sodium is the formation of alkoxide ions. The only alcohol among the options that fits this description is ethanol (C₂H₅OH).

**Hint:** Look for an alcohol that can react with sodium to form an alkoxide.

### Step 2: Determine Compound B
When ethanol (C₂H₅OH) reacts with sodium, it forms sodium ethoxide (C₂H₅ONa). Thus, compound B is C₂H₅ONa.

**Hint:** Remember that alcohols react with sodium to produce alkoxides.

### Step 3: Identify Compound C
Next, we need to determine what compound C is when compound A (ethanol) reacts with phosphorus pentachloride (PCl₅). The reaction of alcohols with PCl₅ typically results in the formation of alkyl chlorides. Therefore, when ethanol reacts with PCl₅, it produces ethyl chloride (C₂H₅Cl).

**Hint:** Consider the reaction of alcohols with PCl₅, which usually yields alkyl chlorides.

### Step 4: Verify the Reaction Between B and C
Now we know:
- A = C₂H₅OH (ethanol)
- B = C₂H₅ONa (sodium ethoxide)
- C = C₂H₅Cl (ethyl chloride)

The question states that B and C react together to give diethyl ether (C₂H₅OC₂H₅). This reaction is indeed possible through an SN2 mechanism where sodium ethoxide reacts with ethyl chloride to form diethyl ether.

**Hint:** Check the compatibility of the products formed when B and C react.

### Conclusion
Now we can summarize the order of compounds A, B, and C:
- A = C₂H₅OH (ethanol)
- B = C₂H₅ONa (sodium ethoxide)
- C = C₂H₅Cl (ethyl chloride)

Thus, the correct order is:
- (A) C₂H₅OH
- (B) C₂H₅ONa
- (C) C₂H₅Cl

From the options provided, the correct answer is:
**(d) C₂H₅OH, C₂H₅ONa, C₂H₅Cl.**

### Final Answer:
**(d) C₂H₅OH, C₂H₅ONa, C₂H₅Cl.**