To determine the correct order of acidic strength among given oxides, we need to understand the nature of the oxides produced by different elements across the periodic table. Oxides are classified into acidic, basic, amphoteric, or neutral based on the element they are derived from and their position in the periodic table.

Acidic oxides are generally formed by non-metallic elements (found on the right side of the periodic table).
Basic oxides are formed by metals (mainly on the left side of the periodic table).
Amphoteric oxides show both acidic and basic properties and are typically formed by metalloids or transition metals.
Neutral oxides show neither acidic nor basic properties.

Let us examine the options:

Option A: Cl₂O₇ > SO₂ > P₄O₁₀

Cl₂O₇ (Dichlorine heptoxide) is a very strong acidic oxide due to the highly electronegative nature of chlorine and its ability to form strong acids (like HClO₄).
SO₂ (Sulfur dioxide) is a moderately strong acidic oxide, capable of forming weak acids like H₂SO₃.
P₄O₁₀ (Phosphorus pentoxide) is also a strong acidic oxide, converting to H₃PO₄ on hydrolysis.

Option B: CO₂ > N₂O₅ > SO₃

CO₂ (Carbon dioxide) forms a weak acid (H₂CO₃) when dissolved in water.
N₂O₅ (Nitrogen pentoxide) is a strongly acidic oxide that hydrolyzes to form nitric acid (HNO₃).
SO₃ (Sulfur trioxide) is an extremely strong acid anhydride, forming H₂SO₄ when combined with water.

Option C: Na₂O > MgO > Al₂O₃

Na₂O (Sodium oxide) is a basic oxide.
MgO (Magnesium oxide) is also a basic oxide, more basic than Na₂O.
Al₂O₃ (Aluminium oxide) is an amphoteric oxide, exhibiting both acidic and basic properties but is not solely acidic.

Option D: K₂O > CaO > MgO

K₂O (Potassium oxide), CaO (Calcium oxide), and MgO are all basic oxides.

From the analysis, it is clear that only Option A: Cl₂O₇ > SO₂ > P₄O₁₀ presents the progressively correct order of acidic strength from strongest to less strong, among mainly acidic oxides. The other options list oxides that are either incorrectly ordered or primarily basic, rather than acidic.

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