Final answer:
The order of increasing acid strength is: H2SeO3 < H2SeO4 < H2SO4. Sulfur (S) is more electronegative than selenium (Se), therefore, H2SO4 is the stronger acid compared to H2SeO4.
Step-by-step explanation:
The order of increasing acid strength is: H2SeO3 < H2SeO4 < H2SO4.
In this case, the acid strength depends on the relative electronegativity of the central atoms of the oxyacids. Since sulfur (S) is more electronegative than selenium (Se), H2SO4 is the stronger acid compared to H2SeO4.