The question below refers to the following graph.

assuming the input of energy continues for another 5 seconds, where will the particle be?

equilibrium
positive maximum
negative maximum
cannot be determined

Equilibrium. The image shows a zero displacement every 5 seconds on the graph. With 5 more seconds it will be at equilibrium again.

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