This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Body Fluids, Subject name: Physiology
Mannitol infusion causes increase in - 
Select and explain. 
A. Blood viscosity, B. Osmolarity, C. Intra-ocular tension, D. Intercranial tension
B: Osmolarity
Answer: B: Osmolarity 
Explanation: Ans. is 'b' i.e., Omolarity o Mannitol is an osmotic agent - It raises osmolarity of plasma.o It causes decrease in :-Blood viscosityIntraocular pressureIntracranial tensiono These effects are due to movement of water (osmotically) from various interstitial space/intracellular space into intervascular space.