Concept:When one partner retires, the remaining partners take the retiring partner's share in their existing profit-sharing ratio, then add it to their old shares to form the new ratio.Explanation:The old ratio is Ade : Tony : Rose = 3:2:1.Therefore, Ade's share = 63, Tony's share = 62, and Rose's share = 61.Ade retires, so his share of 63 is taken by Tony and Rose in their old ratio of 2:1.Tony's gain = 63×32=62.Rose's gain = 63×31=61.New share of Tony = 62+62=64.New share of Rose = 61+61=62.Hence, the new ratio between Tony and Rose = 4:2=2:1.Answer:C. 2:1