Consider the following statements: 1. In a resting neuron, there is difference in electrical charge on either side of surface membrane called potential difference. 2. It is due to unequal distribution of K+ ions and Na+ ions on either side if the membrane. 3. The Na+ concentration inside a cell is about 28 to 30 times > than it is outside 4. The K+ ions concentration is about 14 times > outside than inside. Which of these above statements are correct? (a) 1 only (b) 1, 2 (c) 1, 2, 3 (d) 1, 2, 3, 4