The correct answer is C) motor starting circuits. Time lag fuses, also known as dual-element fuses, are necessary for use in motor starting circuits because of the high inrush current that occurs when a motor is first started. The high initial current draw can cause standard fuses to blow, even though the steady-state operating current may be well within the fuse's rating. Time lag fuses have a delayed response that allows them to withstand the high inrush current without tripping, while still providing overcurrent protection during normal motor operation. The other answer choices are incorrect because main lighting circuits, general alarm circuits, and emergency lighting circuits do not typically experience the same high inrush currents that require time lag fuses for protection.