In induction charging:

Options

A. body to be charged must be a semiconductor
B. body to be charged must be a conductor
C. only type of body can be charged by induction
D. body to be charged must be an insulator

Explanation

**Step-by-Step Solution:**

1. **Understanding Induction Charging:**
- Induction charging is a method of charging an object without direct contact. It involves the influence of a charged object on a neutral object, causing a redistribution of charges within the neutral object.

2. **Identifying the Type of Material:**
- To determine what type of material can be charged by induction, we need to consider the properties of different materials: conductors, insulators, and semiconductors.

3. **Properties of Conductors:**
- Conductors have free-moving electrons that can shift in response to an external electric field. This movement of electrons allows the conductor to become polarized when exposed to a charged object.

4. **Behavior of Insulators:**
- Insulators do not have free-moving electrons. When an insulator is exposed to an electric field, the charges cannot move freely, and thus, the object cannot be charged by induction.

5. **Conclusion:**
- Since the process of induction relies on the movement of free electrons to redistribute charge, the body to be charged must be a conductor. Therefore, the correct answer is that the body to be charged must be a conductor.

**Final Answer:**
The body to be charged in induction must be a conductor.

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