While charging the lead storage battery:

Options

A. `PbSO_4` anode is reduced to Pb
B. `PbSO_4` cathode is reduced to Pb
C. `PbSO_4` cathode is oxidised to Pb
D. `PbSO_4` anode is oxidised to `PbO_2`

Explanation

To solve the question regarding the charging of a lead storage battery, we will analyze the reactions occurring at the anode and cathode during the charging process.

### Step-by-Step Solution:

1. **Identify the Components of the Lead Storage Battery:**
- The lead storage battery consists of lead (Pb) as the anode and lead dioxide (PbO2) as the cathode. The electrolyte is typically a sulfuric acid solution (H2SO4).

2. **Understand the Charging Process:**
- During the charging process, electrical energy is supplied to the battery, reversing the chemical reactions that occur during discharge.

3. **Anode Reaction:**
- At the anode (negative plate), lead sulfate (PbSO4) is converted back to lead (Pb). The reaction can be represented as:
\[ \text{PbSO}_4 + 2e^- + 2H^+ \rightarrow \text{Pb} + \text{H}_2\text{SO}_4 \]
- Here, lead sulfate is reduced to lead, and hydrogen ions are produced.

4. **Cathode Reaction:**
- At the cathode (positive plate), lead sulfate (PbSO4) is converted back to lead dioxide (PbO2). The reaction can be represented as:
\[ \text{PbSO}_4 + 2e^- \rightarrow \text{PbO}_2 + \text{H}_2\text{SO}_4 \]
- In this reaction, lead sulfate is oxidized to lead dioxide.

5. **Overall Reaction:**
- The overall reaction during the charging of the lead storage battery can be summarized as:
\[ 2\text{PbSO}_4 + 2H_2O \rightarrow 2\text{Pb} + \text{PbO}_2 + 2\text{H}_2\text{SO}_4 \]
- This shows the conversion of lead sulfate back to lead and lead dioxide, with the regeneration of sulfuric acid.

6. **Conclusion:**
- Thus, during the charging of a lead storage battery, lead sulfate is reduced to lead at the anode, while at the cathode, lead sulfate is oxidized to lead dioxide.