Glucose is an organic compound and this is not ionised while BaCl2 and NaCl are inorganic compounds and they are strong electrolytes and are normally 100% ionised at normal dilution. BaCl2⇌Ba2++2Cl− NaCl⇌Na++Cl− ∵ Osmotic pressure is a colligative property and hence, depends on the number of ions.
So, decreasing order of osmotic pressure is BaCl2>NaCl> glucose