Alright, so basically it goes like this:
The farther left you go on the number line, the less value the number holds.
The farther right you go on the number line, the more value the number holds.
-3.5 is as FAR left as any of these numbers, this means it's the number with the least value. It'll be your first number.
-1/4 is your next one. This is before the -3.5, meaning on the number line, it's a little to the right of the -3.5. So, this'll be your number with the SECOND lowest value.
1/3 is a positive number, meaning it's after the 0, but barely. It's not a whole number, which is why it's a fraction. Even though it's considerably bigger than the other 2 numbers I just listed, it's still pretty low, so this is your number with the THIRD lowest value.
2 is a positive number. It holds the most value, because it is the farthest number out of these to the right of the 0.
Your correct order is B: -3.5, -1/4, 1/3, 2
This is Least to Greatest.
~Hope this helps buddy!