Find the smallest 6-digit number that can be formed by the digits 9, 6, 0, 5, 8 and 1.

The correct option is B 1, 05, 689
To form the smallest number (without repetition of digits) from the given digits, write the digits in ascending order and place commas after periods.
0 < 1< 5 < 6 < 8< 9.
Remember that a number cannot start with 0 in the leftmost place.
Hence we will place it 2nd while forming the number. The required number is therefore 1,05,689.