Five isomeric p-subsituted aromatic compounds (A) to (E ) with molecular formula `C_(8)H_(8)O_(2)` are given for identifyication. Based on the following observition, give the strucctures of the compounds.
i. Both (A) and (B) form a silver mirror with Tollens reagent, (B) also gives a positive test with neutral `FeCl_(3)` solution.
ii. (C ) gives positive iodoform test.
iii. (D) is readily extracted in aqueous `NaHCO_(3)` solution.
iv. (E ) on acid hydrolysis gives 1,4-dihydroxy benzene.
Compound (D) is:

Options

A.
B.
C.
D.

Explanation

To identify the structure of compound (D) from the given observations, we can follow these steps:

### Step 1: Analyze the Observations
We have five isomeric p-substituted aromatic compounds (A to E) with the molecular formula C8H8O2. The observations provided will help us deduce the structures of these compounds.

### Step 2: Identify the Key Observation for Compound (D)
The observation for compound (D) states that it is "readily extracted in aqueous NaHCO3 solution." This is a significant clue because only carboxylic acids react with sodium bicarbonate to produce carbon dioxide gas (CO2), which indicates that compound (D) must contain a carboxylic acid functional group (-COOH).

### Step 3: Evaluate the Possible Structures
Given the molecular formula C8H8O2, we can consider the possible structures that include a carboxylic acid group. The presence of a carboxylic acid suggests that compound (D) could be a para-substituted benzoic acid derivative.

### Step 4: Check the Options
From the options provided, we need to identify which compound contains a carboxylic acid group.

- **Option A**: Contains an ether group.
- **Option B**: Contains a carboxylic acid group (COOH) and a methyl group at the para position.
- **Option C**: Contains a double bond and an ether group.
- **Option D**: Contains an amine group.

Among these, only **Option B** has the carboxylic acid group, which aligns with the observation that compound (D) is extracted in aqueous NaHCO3.

### Step 5: Confirm the Structure of Compound (D)
The structure of compound (D) is therefore **para-methylbenzoic acid** (also known as p-toluic acid), which has the following structure:

```
COOH
|
C6H4-CH3
```

### Conclusion
Based on the analysis, the structure of compound (D) is **para-methylbenzoic acid**.

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