The correct option is D <
Clearly, both the numbers have equal number of digits.
At the leftmost place, both have the same digit i.e. 2 each.
At the 2nd,3rd and 4th place plce from leftside, both again have the same digits i.e. 3,4 and 5 respectively.
At the 5th place from left, the first number has digit 7 and second number has digit 9.
Since 7<9.
So, 23457 < 23459.