AIIMS 2018 Biology Nerve Impulse Transmission MCQ Question

During rest, the sodium-potassium pump (Na⁺/K⁺ ATPase) actively transports 3 Na⁺ ions out of the neuron and 2 K⁺ ions into the neuron, resulting in a net loss of positive charge inside the cell. This creates a resting membrane potential, as more Na⁺ is pumped out than K⁺ is taken in, making option A correct. Option B is incorrect because Na⁺ is not pumped in without an exchange; it is always exchanged with K⁺. Option C is incorrect because the pump does not exchange equal amounts of Na⁺ and K⁺, and option D is incorrect as it misrepresents the direction of ion movement, suggesting more Na⁺ is pumped in than out.