Sen treats argumentation as a positive value. Argumentation sparked dissent and shaped Indian politics to a large extent. He even claimed that argumentation was an important contribution to the development of democracy in India. Argumentation supports the opinions of ordinary people, which helps maintain democracy in our country. Therefore, Sen believes that argumentation is extremely important for the normal operation of democracy.
A compound (A) with molecular formula $C_4H_9I$ which is a primary alkyl halide, reacts with alcoholic KOH to give compound (B). Compound (B) reacts with HI to give (C) which is an isomer of (A). When (A) reacts with Na metal in the presence of dry ether, it gives a compound (D), C8H18, which is different from the compound formed when n-butyl iodide reacts with sodium. Write the structures of A, (B), (C) and (D) when (A) reacts with alcoholic KOH.