Correct option is D
In a lead-acid battery, the positive plate material is originally lead dioxide (PbO₂), which is an active material responsible for the electrochemical reactions. During operation, especially while discharging, a chemical reaction takes place between the electrolyte (sulphuric acid, H₂SO₄) and both plates. As a result, both the positive and negative plates tend to convert into lead sulfate (PbSO₄).
However, many exam questions (like this one) focus on the identification of the positive plate material itself, rather than its temporary chemical state during discharge. In that context, the positive plate is defined by its original active material, which is PbO₂.
