In the given reaction
`COOH-(CH_2)_(5)-COOH overset(Delta)(rarr)(X)`, 'X' will be

Options

A. Monobasic acid
B. Acid anhydride
C. Cyclic ketone
D. Open chain ketone

Answer

To solve the problem, we need to analyze the reaction of the dicarboxylic acid given in the question, which is represented as COOH-(CH₂)₅-COOH. This compound is a dicarboxylic acid with a total of 7 carbon atoms (5 from the CH₂ groups and 2 from the carboxylic acid groups).

### Step-by-Step Solution:

1. **Identify the Structure of the Dicarboxylic Acid**:
The compound can be represented as:
\[ HOOC-(CH_2)_5-COOH \]
This is hexanedioic acid (also known as adipic acid).

2. **Heating the Dicarboxylic Acid**:
When dicarboxylic acids are heated, they can undergo a process called dehydration, where water (H₂O) and carbon dioxide (CO₂) are released.

3. **Formation of Cyclic Structure**:
In the case of hexanedioic acid, when heated, it can form a cyclic compound. The carboxylic acid groups can react with each other, leading to the loss of CO₂ and H₂O, resulting in the formation of a cyclic ketone.

4. **Identify the Product**:
The cyclic structure formed from hexanedioic acid will have a six-membered ring with one carbonyl (C=O) group. This cyclic compound is known as a cyclic ketone.

5. **Final Product**:
The final product 'X' from the reaction COOH-(CH₂)₅-COOH upon heating will be a cyclic ketone, specifically 1,4-cyclohexanedione.

### Conclusion:
Thus, the compound 'X' formed from the reaction is a cyclic ketone.

---