Instead of discussing the proper method here, I am going to write the fastest method to achieve the result:
So we know, all numbers are made up of digits from 0-9 so no need to worry about miscounting we just need to count the digits in all the number to arrive at 1012
Given: page numbering starts from 3,
We know that for a single-digit number the number of time the digits 0-9 occur is 1, so counting from 3 to 9 there are 7 page-numbers
so 7*1 = 7 -> (1)
Similarly, for 2 digit numbers there can 90 page-numbers
so 90*2 = 180 -> (2)
Now seeing the options we can see that no option is a four-digit or two-digit page number, so all two-digit numbers are possible.
Now, removing (1) & (2) from 1012 will get us the number of times digits are used in 3-digit numbers
i.e. 1012 - 7 - 180 = 825 -> (3)
Now if there are x three-digit numbers then there will be 3x digits used
Therefore 3x = 825
x = 275
Counting from 100, 374 is the 275th number
Therefore the correct option is (A)