Gunmen loyal to Bosnian Serb nationalist leader Radovan Karadzic conquered 70% of Bosnia with their arsenal of tanks, aircraft and howitzers bequeathed by the Yugoslav army.
Can we infer the following?
Gunmen loyal to Bosnian Serb nationalist leader Radovan Karadzic conquered less than 83% of Bosnia.

pick from the following.
 a). Yes.
 b). It's impossible to say.
 c). No.
The answer is:
a).