Concept:Electric cells are grouped into primary and secondary cells depending on whether they can be recharged.Explanation:Primary cells cannot be recharged once their chemicals are used up.Secondary cells can be recharged and reused many times.A major advantage of secondary cells is that they have very low internal resistance.Low internal resistance allows them to supply a larger current more efficiently.Therefore, the only correct statement is the one about secondary cells having very low internal resistance.Answer:D. Secondary cell has a very low internal resistance.