The compound `C_8H_9Cl(A)` on treatments with KCN followed by hydrolysis gives `C_9H_10O_2(B)`.Ammonium salt of B on dry distillation yields C.Which reacts with alkaline solution of bromine to gives `C_8H_11N`.(D)Another compound E is obtained by the action of nitrous acid on D. E on oxidation gives F which gives the inner anhydride G on heating. The Compound A is :

Options

A.
B.
C.
D.

Explanation

To solve the problem step by step, we will analyze the given information about the compounds and their transformations.

### Step 1: Identify Compound A
The compound `C_8H_9Cl(A)` has 8 carbons, 9 hydrogens, and 1 chlorine atom. The presence of chlorine suggests that it is likely a chlorinated aromatic compound. The possible structure could be a chlorobenzene derivative with an alkyl group.

**Hint:** Look for a structure that includes a benzene ring and a side chain that fits the molecular formula.

### Step 2: Reaction with KCN and Hydrolysis
When compound A reacts with KCN followed by hydrolysis, it converts to `C_9H_{10}O_2(B)`. This suggests that the chlorine is replaced by a cyanide group, which upon hydrolysis forms a carboxylic acid.

**Hint:** Consider how the chlorine can be replaced by a cyanide group and how hydrolysis would convert that to a carboxylic acid.

### Step 3: Formation of Compound C
The ammonium salt of B undergoes dry distillation to yield compound C. This indicates that compound B is likely an amide (since it forms an ammonium salt), and upon dry distillation, it would yield an amine.

**Hint:** Think about the structure of B and how it can be converted to an amine through dry distillation.

### Step 4: Reaction of Compound C with Bromine
Compound C reacts with an alkaline solution of bromine to give `C_8H_{11}N(D)`. This suggests that compound C is an amine that can undergo the Hofmann degradation reaction to yield a primary amine.

**Hint:** Identify the structure of compound C and how it can be transformed into an amine.

### Step 5: Formation of Compound E
Compound D, which is a primary amine, reacts with nitrous acid to form compound E. This reaction typically converts primary amines to alcohols.

**Hint:** Recall the reaction of primary amines with nitrous acid and how it leads to the formation of alcohols.

### Step 6: Oxidation of Compound E
Upon oxidation, compound E gives compound F. The oxidation of an alcohol typically leads to the formation of a carbonyl compound (aldehyde or ketone).

**Hint:** Consider what type of carbonyl compound would be formed from the oxidation of the alcohol derived from compound E.

### Step 7: Formation of Inner Anhydride G
Finally, compound F can be heated to give an inner anhydride G. This suggests that F has two carboxylic acid groups that can condense to form an anhydride.

**Hint:** Think about the structure of F and how it can lead to the formation of an anhydride upon heating.

### Conclusion
After analyzing all the steps, the compound A is likely to be **4-chlorobutanoic acid** or a similar structure that fits the molecular formula `C_8H_9Cl`. This compound undergoes the described transformations to yield the final products.

**Final Answer:** The compound A is **4-chlorobutanoic acid** or a similar derivative.