Bauxite ore is generally contaminated with impurity of oxides of
two elements `X` and `Y`. Which of the following statement is correct?

Options

A. `X` is a non-metal and belongs to the third period while `Y` is a metal and belongs to the fourth period.
B. One of two oxides has three-dimensional polymeric structure.
C. both (a) and (b) are correct.
D. None of the above

Explanation

To solve the question regarding the impurities found in bauxite ore, we will analyze the statements provided and determine which one is correct.

### Step-by-Step Solution:

1. **Identify the Composition of Bauxite:**
- Bauxite ore is primarily composed of aluminum oxide, specifically in its hydrated form, which is represented as Al2O3·2H2O.

2. **Identify Common Impurities:**
- Bauxite is typically contaminated with impurities such as silicon dioxide (SiO2), iron(III) oxide (Fe2O3), and titanium dioxide (TiO2).
- For the purpose of this question, we will consider SiO2 as oxide X and Fe2O3 as oxide Y.

3. **Classify the Elements:**
- Silicon (Si) in SiO2 is a non-metal and belongs to the p-block of the periodic table, specifically in the third period.
- Iron (Fe) in Fe2O3 is a metal and belongs to the d-block of the periodic table, specifically in the fourth period.

4. **Evaluate the Statements:**
- **Statement A:** "X is a non-metal belongs to 3rd, Y is a metal."
- This statement is correct because Si is a non-metal in the third period and Fe is a metal in the fourth period.
- **Statement B:** "One of the two oxides has a three-dimensional polymeric structure."
- This statement is also correct. SiO2 can form a polymeric structure (like chain or sheet silicates), while Fe2O3 has an ionic structure.
- **Statement C:** "Both A and B are correct."
- Since both statements A and B are correct, this statement is also correct.

5. **Conclusion:**
- The correct answer is that both statements A and B are correct.

### Final Answer:
Both A and B are correct.

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