The main constituents of cement are :

Options

A. calcium oxide, silicon dioxide, Aluminium oxide
B. calcium oxide, Iron oxide, Sulphur dioxide
C. magnesium oxide, Silicon dioxide, Aluminium oxide
D. none of these

Answer

**Step-by-Step Solution:**

1. **Identify the Main Constituents of Cement**:
- The primary ingredient in cement is lime, which is chemically known as calcium oxide (CaO).

2. **List Other Key Components**:
- In addition to lime, Portland Cement specifically includes silica (SiO2) and alumina (Al2O3) as significant constituents.

3. **Summarize the Main Constituents**:
- Therefore, the main constituents of Portland Cement can be summarized as:
- Calcium Oxide (CaO)
- Silica (SiO2)
- Alumina (Al2O3)

4. **Conclude the Answer**:
- The main constituents of cement are lime (CaO), silica (SiO2), and alumina (Al2O3).

**Final Answer**: The main constituents of cement are Calcium Oxide (CaO), Silica (SiO2), and Alumina (Al2O3).

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