Answer: The correct answer is
![Al_2O_3](https://img.qammunity.org/2020/formulas/chemistry/middle-school/slfos4n5ms779dquqd6mfomuu2s6yzp9hd.png)
Step-by-step explanation:
Aluminium is the 13th element of the periodic table with electronic configuration of
![1s^22s^22p^63s^23p^1](https://img.qammunity.org/2020/formulas/chemistry/middle-school/60892ufl66c7u90p109eldg755kui6fy6u.png)
This element looses 3 electrons and shows an oxidation state of +3.
Oxygen is the 8th element of the periodic table with electronic configuration
![1s^22s^22p^4](https://img.qammunity.org/2020/formulas/chemistry/middle-school/rnpl8dbr8topswjtty6vgfawasfrwl0cig.png)
This element will gain 2 electrons and shows an oxidation state of -2.
By criss-cross method, the oxidation state of aluminium and oxygen gets revered and they form the coefficients of the compound.
Hence, the compound formed will have the chemical formula of
![Al_2O_3](https://img.qammunity.org/2020/formulas/chemistry/middle-school/slfos4n5ms779dquqd6mfomuu2s6yzp9hd.png)