I believe the answer is C.
It would decrease as their prime food source would be taken away. This would result in a decline in population as the birds wouldn’t have sufficient food.
Hope that helps. :)
The answer is Na + is entering the cell and the K + is leaving, during the depolarization phase of the action potential open Na + channels allow Na + ions to diffuse into the cell. This inward movement of positive charge makes the membrane potential more positive. The depolarization phase is a positive response sequence where open Na + channels cause depolarization which in re-occurrence causes more voltage gated Na+ channels to open.