14) D

The most number of elements that would need to change would be from the digit that has the least elements to the digit which requires the most changes from the digit which has the least elements. 

Digit which has the least elements = 1
1 has two elements. 

To change 1 to 0, we need to add 4 elements

To change 1 to 2, we need to change 5 elements

To change 1 to 3, we need to add 3 elements

To change 1 to 4, we need to add 2 elements

To change 1 to 5, we need to change 5 elements

To change 1 to 6, we need to change 6 elements

To change 1 to 7, we need to add 1 elements

To change 1 to 8, we need to add 5 elements

To change 1 to 9, we need to add 4 elements

Hence the maximum number of elements that change from one number to another is 6 (from 1 to 6).

Leave a Reply