Correct option is B
In this question following logic is followed-
Option (a) 1000, 125 → 103, 53
Option (b) 216, 49 → 63, 72
Option (c) 1728, 216 → 123, 63
Option (d) 512, 64 → 83, 43
In the all-option 1st and 2nd number are a cube number except option (b) and also the 2nd number is without cube is the half of the 1st number.
Thus, the correct option is (b).