Step 1: Recall the general oxide trend down Group 13.
Acidic character of an oxide generally falls, and basic or amphoteric character rises, as metallic character increases down the group, though the trend is not perfectly smooth for every member.
Step 2: Classify each oxide individually.
Boron is a genuine non-metal, so $\text{B}_2\text{O}_3$ is acidic and dissolves in water to give boric acid. Aluminium, despite being a metal, has an oxide, $\text{Al}_2\text{O}_3$, that dissolves in both acids and bases, so it is amphoteric. Gallium follows aluminium's pattern, and $\text{Ga}_2\text{O}_3$ is also amphoteric.
Step 3: Order them as asked, Al, B, Ga.
Aluminium's oxide is amphoteric, boron's is acidic, and gallium's is amphoteric.
Final answer: Option 2, amphoteric, acidic, amphoteric.