The correct answer is D) Rotor slip is dependent upon the motor load. In a basic squirrel-cage induction motor, the rotor slip is directly dependent on the motor's load. As the load on the motor increases, the rotor speed decreases, resulting in greater slip between the rotating magnetic field and the rotor. Conversely, as the load decreases, the rotor speed increases, and the slip decreases. The other options are incorrect because: A) An increase in motor load results in greater slip, not less. B) A decrease in rotor speed does not produce a weaker magnetic field, as the magnetic field strength is determined by the stator winding design and supply voltage. C) A decrease in rotor speed results in greater current draw, not less, due to the increased slip.