Is energy released or absorbed during the formation of a solution?

Energy can be released and absorbed during the formation of a solution, not one or the other. When a solute interacts with the solvent, energy is absorbed so the solvent can overcome the intermolecular bonds of the solute and energy is released, most commonly, in the form of heat, light, or a gaseous byproduct.

Ohm's law tells you that i = v/r where v is equivalent voltage and r is equivalent resistance of the circuit
since all circuits have the same voltage, your question is really asking which circuit has the lowest total resistance, since the lower the resistance, the higher the current
circuit a has a resistance of 5 ohms; circuit c is in series so has a resistance of 10 ohms; circuit b is in parallel and therefore has a resistance of 2.5 ohms (review your notes on adding resistances in parallel and series); therefore b has the highest current