Substances through which electricity cannot flow are called :

Options

A. Conductors
B. Insulators
C. Wires
D. Battery

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about substances that do not allow electricity to flow through them.

2. **Identifying Key Terms**: The key terms in the question are "substances," "electricity," and "cannot flow."

3. **Options Analysis**: The options provided are:
- Conductor
- Insulator
- Wire
- Battery

4. **Defining Conductors and Insulators**:
- **Conductors**: These are materials that allow electricity to flow through them easily. Examples include metals like copper and aluminum.
- **Insulators**: These are materials that do not allow electricity to flow through them. Examples include rubber, plastic, wood, and glass.

5. **Eliminating Incorrect Options**:
- **Wires**: Wires are typically made of conductive materials and are used to carry electricity, so they cannot be the answer.
- **Battery**: A battery is a source of electrical energy and does not fit the description of a substance that prevents electricity from flowing.

6. **Conclusion**: Since insulators are defined as substances that do not allow electricity to flow, the correct answer to the question is **insulator**.

**Final Answer**: Substances through which electricity cannot flow are called **insulators**.

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