Compound (A), `C_(5)H_(11)NO` is not soluble in cold dilute alkaline or acidic solutions. When (A) is refluxed in NaOH solution , a gas (B) is evolved and a salt (C) is formed. Acetyl chloride reacts with (B) to give (D) `C_(4)H_(9)NO`. (B) reacts with `HNO_(2)` to give a yellow oil (E ). Give the structures of (A) to (E ) with reason.