An acidic compound `(A) (C_4 H_8 O_3)` loses its optical activity on strong heating yielding `(B) (C_4 H_6 O_2)` which reacts readly with `KMnO_4`. `(B)` forms a dervative `( C)` with `SOCl_2` which on reaction with `(CH_3)_2 NH` gives `(D)`. The compound `(A)` on oxidation with dilute chromic acid gives an unstable compound `(E)` which decarboxylates readily to give `(F) (C_3 H_6 O)`. The compound `(F)` gives a hydrocarbon `(G)` on treatment with amalgamated `Zn` and `HCl`. Give the structures of `(A)` to `(G)` with proper reasoning.

Explanation

To solve the problem step by step, we will identify the structures of compounds A to G based on the information provided in the question and the reasoning outlined in the video transcript.

### Step 1: Identify Compound (A)
Given that compound (A) has the molecular formula \(C_4H_8O_3\) and is optically active, we can deduce the following:
- The degree of unsaturation is calculated as:
\[ \text{Degree of Unsaturation} = \frac{2C + 2 - H}{2} = \frac{2(4) + 2 - 8}{2} = 1 \]
...