Decreasing Stability order of given I, II, III, IV (in order) A)IV>I>II>III B)I>IV>III>II C)I>II>IV>III D)IV>II>I>III (My Answer) Since the IV is most stable, only A and D answers are worth checking. They only differ by stability order of I and II. Then I checked by determining their stability due to hyperconjugation. I has HC3 while II has HC4, hence my answer D. But the correct answer is A. Any suggestions, whether my answer or provided answer is correct?