This is a tricky proposition.
Usually distinguish from and distinguish between are acceptable. But, if we are concerned about GMAT, then we have to go according to what they say is correct!
Also distinguish from seems more appropriate when one says "Distinguish car from bike"
and "Distinguish between cars or storms or trees"(similar properties)
Hence, here I prefer "distinguish between X and Y" idiom.
Before that,let us see, what other things can be incorrect here:
A=Incorrect, distinguish word has to be included.
After the comma the usage of which and perhaps
Here I feel the usage of which is important!
Whether whatever information about the storms is essential or non essential?
Based on such things we can use POE and arrive at the final answer!
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
