Final answer:
Out of the given options, sodium oxide (Na2O) is the only basic oxide. CO2 and SO3 are acidic oxides.
Step-by-step explanation:
Out of the given options, the oxide that is basic is c) Na2O. Sodium oxide (Na2O) is a basic oxide because it reacts with water to form a strongly basic solution, sodium hydroxide (NaOH). This reaction can be represented as:
Na2O + H2O → 2NaOH
In contrast, a) CO2 and b) SO3 are acidic oxides because they react with water to form acidic solutions. For example, carbon dioxide (CO2) reacts with water to form carbonic acid (H2CO3), which is a weak acid:
CO2 + H2O → H2CO3