Total number of numerals = 10
Total number of numerals to be used = 6
We are to find the number of different codes that can be formed and those can be found by permutations.
We have to find the permutations of 10 numerals taken 6 at a time. So we are to find 10P6.
10P6 = 151200
So, 151200 different codes can be formed.
So the answer to this question is option A