Which channels are primarily responsible for maintaining the resting membrane potential?

The maintenance of resting membrane potential is primarily attributed to the leaky potassium channels. These channels allow potassium ions (K+) to move out of the cell, which is crucial for establishing a negative charge inside the cell compared to the outside environment. As potassium ions diffuse out, the cell becomes more negatively charged, contributing significantly to the resting membrane potential typically ranging from -70 to -90 mV.

In contrast, fast sodium channels are primarily involved in the depolarization phase of action potentials rather than resting membrane potential. Calcium channels also play a role in various signaling pathways and muscle contractions, but they do not contribute significantly to the resting membrane potential. Therefore, the leaky potassium channels are essential for stabilizing the resting state of the membrane by allowing the passive flow of potassium ions, making option B the correct choice.