Identify the final product in the given reaction:
`Ph-CH_(2)COOH underset((ii) :COH)overset((i)P_("red")+Br_(2))to X overset(H^(+),Delta)(to) Y`

Options

A. A) `Ph-CH_(2)-underset(O)underset(||)(C)-O-CH_(2)-Ph`
B.
C. C) `Ph-CH_(2)-underset(O) underset(||)(C)-O-underset(O) underset(||)(C)-CH_(2)Ph`
D.

Explanation

To identify the final product in the given reaction, we will follow the steps outlined in the video transcript. Let's break it down step by step.

### Step 1: Identify the starting material
The starting material is `Ph-CH2COOH`, which is benzoic acid with a benzene ring (Ph) attached to a methylene group (CH2) and a carboxylic acid (COOH).

### Step 2: Reaction with Red Phosphorus and Br2
The first part of the reaction involves treating `Ph-CH2COOH` with red phosphorus and bromine (Br2). This reaction leads to the substitution of hydrogen atoms in the methylene group with bromine atoms.

**Reaction:**
\[ \text{Ph-CH}_2\text{COOH} + \text{Br}_2 \xrightarrow{\text{P (red)}} \text{Ph-CHBr-COBr} + \text{H}_2\text{O} \]

Here, two bromine atoms replace one hydrogen atom from the methylene group and one hydroxyl group (OH) from the carboxylic acid, forming a dibrominated compound.

### Step 3: Reaction with COH (Formaldehyde)
Next, the product `Ph-CHBr-COBr` is reacted with formaldehyde (COH). During this reaction, the bromine atoms are replaced by hydroxyl groups (OH).

**Reaction:**
\[ \text{Ph-CHBr-COBr} + \text{COH} \rightarrow \text{Ph-CH(OH)-COO}^- + \text{Br}^- \]

In this step, the bromine atoms are replaced by hydroxyl groups, leading to the formation of a compound with a carboxylate ion.

### Step 4: Protonation and Heating
The resulting compound undergoes protonation and heating. This process typically leads to the formation of a cyclic structure or a ring.

**Final Reaction:**
Upon heating and protonation:
\[ \text{Ph-CH(OH)-COO}^- \xrightarrow{H^+, \Delta} \text{Cyclic structure} \]

The final product is a cyclic compound formed from two molecules of the intermediate compound.

### Final Product
The final product Y is a cyclic compound formed from the reaction of two molecules of the intermediate product after protonation and heating.

### Summary of the Final Product
The final product is a cyclic structure that can be represented as:
\[ \text{Ph-CH=CHO-CH=CO-Ph} \]