We can eliminate options by looking at the sentence:
Option 2 is wrong because it starts with "employees with whom they deal", which doesn't make sense ("they" haven't been defined)!
Option 3 is wrong because it starts with "services", which is also incorrect.
Option 4 is wrong because it puts "for organizations which provide" at the end, which is not a complete thought... provide what? hein? baingain?
Only option 1 puts the parts in a logical order: (A), (B), (D), (C).