let's take three diffrent natural no = 2, 3, 4
two digit no formed by these digits are : 23, 32 , 42, 24, 34, 43
sum of these two digits no = 23 + 32 + 42 + 24 + 34 + 43 = 198
sum of those three digits = 2+ 3 + 4 = 9
so, 198 / 9 = 22
So, "D is correct"