3 + 1 : (8)3 + 1Similarly, I. 26 : 342 = (5)2 + 1 : (7)3 - 1 II. 126 : 344 = (5)3 + 1 : (7)3 + 1III. 64 : 217 = (8)2 : (6)3 + 1IV. 49 : 730 = (7)2 : (9)3 + 1So, option (2) is followed this pattern but other three OPTIONS not followed.Hence, "126 : 344" is the correct answer.