An organic compound `(A), C_(8)H_(4) O_(3)` in dry benzene in the presene of anhydorus `AlCl_(3)` gives compound `(B)`. Compound `(B)` on treatment with `PCl_(5)` followed by reaction with `H_(2)//Pd (BaSO_(4))` gives compound `(C)` which on reaction with hydrazine gives a cyclised compound `(D),(C_(14) H_(10) N_(2))` Idenyify `(A),(B),(C)` and `(D)`. Explain the formation of `(D)` from `(C)`.

Explanation

To solve the problem step by step, we will identify the compounds A, B, C, and D based on the given reactions and their molecular formulas.

### Step 1: Identify Compound (A)
Given that compound (A) has the formula \( C_8H_4O_3 \), we can deduce its structure. The presence of three oxygen atoms suggests that it might contain a carboxylic acid or an ester group. A possible structure for compound (A) is:

- **Compound (A)**: 1,2-benzenedicarboxylic acid (Phthalic acid)

### Step 2: Reaction of Compound (A) to form Compound (B)
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