Group comprising all metals is

Options

A. III A
B. IV A
C. VII A
D. II A

Answer

To determine which group comprises all metals, we need to analyze the options provided: 3A, 4A, 7A, and 2A.

### Step-by-Step Solution:

1. **Understanding the Groups**:
- The periodic table is divided into groups and periods. Groups are the vertical columns, and elements within the same group often share similar properties.

2. **Identifying the Groups**:
- **3A (Group 13)**: This group includes elements like Boron (B), Aluminum (Al), Gallium (Ga), Indium (In), and Thallium (Tl). It contains both metals and non-metals (Boron is a non-metal).
- **4A (Group 14)**: This group includes Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), and Lead (Pb). It also contains both metals (Sn, Pb) and non-metals (C, Si).
- **7A (Group 17)**: This group is known as the halogens, which includes Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At). All these are non-metals.
- **2A (Group 2)**: This group is known as the alkaline earth metals and includes Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), and Barium (Ba). All these elements are metals.

3. **Conclusion**:
- From the analysis, we can see that the only group that comprises all metals is **2A (the alkaline earth metals)**.

### Final Answer:
The group comprising all metals is **2A**.

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