The most common pH of a carbonated beverage (soda) that can cause dental erosion:

Most carbonated sodas have a pH of approximately 2.5–3.5, making them highly acidic and capable of causing dental erosion. The critical pH for enamel dissolution is approximately 5.5. Colas (like Coca-Cola) average around pH 2.5; citrus sodas may be even lower. Regular consumption creates a chronic acidic oral environment promoting enamel erosion. The question asks for the 'most common pH' which is pH 2.5 as the most clinically recognized value for soft drinks.