A number arrangement machine, when
given a particular input , rearranges it following a particular
rule. The following is the illustration of the input and the stages of arrangement.
`{:("Input : 245,316,436,519,868,710,689"),("Step I :710,316,436,519,868,245,689"),("Step II :710,316,245,519,868,436,689"),("Step III: 710,316,245,436,868,519,689"),("Step IV: 710,316,245,436,519,868,689"):}`
Step IV is the last step of input .
If following is the second step for an input, what will be
the fourth step ?
Step II : 620,415,344,537,787,634,977

Options

A. `620,415,344,537,634,787,977`
B. `620,415,344,634,537,787,977`
C. `620,415,344,634,787.537,977`
D. Can't be determined

Answer

B

Explanation

Here, the rule followed is: the sum of the digits is calculated. Then in step I, the number with lowest sum of its digits inter number. (If the first number has already the lowest the number with second lowest sum of its digit in second number.] The process continues until the numb ascending order on the basis of their sum of digits.