Quantities must have different unit before they can be added or subtracted true or false

That statement is a false and untrue example of prevarication.

The truth is exactly the opposite.  Quantities CAN NOT be added
or subtracted when their units are different.  Before addition or
subtraction can be attempted, the quantities must have the SAME
units, and if that can't be arranged, then the quantities can't be
added or subtracted.

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

The object's initial distance above the groundthe object's initial velocity