Correct Answer - A
`DU` in `A=((2n_(C )+2)-n_(H))/2=((2xx4+2)-8)/2=1^(@)`
(Due to `(-COOH)` group)
Compount (B) is unstable and losed `CO_(2)`, it shows (B) must contain beta-keto acid, which account for three oxygen atoms in (A) and (B).
(A) must contain beta-hydroxy acid which on oxidation with `PC C` gives (B) `(beta-"keto acid")`.
Therefore, structure of (A) `implies`
Conversion of `MeCHO` to `MeCOMe` (Acetone):
