General Studies · Number Analogy

Two sets of numbers are given below. In each set, a specific mathematical operation on the first number results in the second, on the second results in the third, and on the third results in the fourth. Which of the options follows the same pattern? Pattern: 68 - 136 - 121 - 363 ; 29 - 58 - 43 - 129 (Note: Operations must be performed on whole numbers only, not on individual digits.)