Final answer:
The ionic compound Al2Se3 is correctly named as aluminum selenide, which is choice (a) from the given options.
Step-by-step explanation:
The ionic compound Al2Se3 is named aluminum selenide. In this compound, aluminum acts as a cation with a charge of +3 (Al3+), and selenium acts as an anion with a charge of -2 (Se2-).
Since the compound is ionic, it is not necessary to specify the number of atoms of each element in the name as we would with molecular (covalent) compounds. The correct answer to the naming of Al2Se3 is option (a), aluminum selenide.