The normal dehydrating agent, which used in a laboratories:-

Options

A. `MgCO_(3)`
B. `CaF_(2)`
C. `MgF_(2)`
D. `CaCl_(2)`

Explanation

**Step-by-Step Solution:**

1. **Understanding Dehydrating Agents**:
- A dehydrating agent is a substance that removes water or moisture from other substances. It is essential in various laboratory processes where the presence of water can interfere with reactions or product formation.

2. **Characteristics of a Good Dehydrating Agent**:
- A suitable dehydrating agent should have a strong affinity for water. This means it should readily absorb water molecules from its surroundings.
- It should preferably be anhydrous, meaning it should not contain any water in its structure.

3. **Identifying Common Dehydrating Agents**:
- Common dehydrating agents include substances like sulfuric acid, phosphorus pentoxide, and calcium chloride. However, the focus here is on the one that is most commonly used in laboratories.

4. **Focusing on Calcium Chloride**:
- Among the dehydrating agents, anhydrous calcium chloride (CaCl₂) is widely used in laboratories. It is known for its strong affinity for water and is effective in drying various organic solvents.

5. **Applications of Calcium Chloride**:
- Calcium chloride is used to dry solvents such as acetone, ethers, and various esters. Its ability to absorb moisture makes it a practical choice for laboratory drying processes.

6. **Conclusion**:
- Based on the properties and applications discussed, the normal dehydrating agent used in laboratories is **calcium chloride**.

**Final Answer**: Calcium chloride (CaCl₂)

---