Which of the Following Aqueous Solutions Has the Highest Osmotic $\circ$

Multiple Choice

Which of the following aqueous solutions has the highest osmotic pressure at 25 ^$\circ$ C (assume 100% dissociation for all soluble ionic compounds)

A) 0.15m K₃PO₄
B) 0.20m KI
C) 0.25m K₂CO₃
D) 0.30m NH₄NO₃
E) 0.45m C₁₂H₂₂O₁₁