The correct answer is C. Lewis Acid.
A Lewis acid is a chemical species that accepts an electron pair to form a Lewis adduct. Lewis acids are typically electron-deficient species, such as metal ions and molecules with multiple bonds.
Aluminium chloride is a Lewis acid because it can accept an electron pair from a Lewis base. For example, aluminium chloride can react with ammonia to form a Lewis adduct:
$$AlCl_3 + :NH_3 \to [AlCl_3(NH_3)]^+$$
In this reaction, the ammonia molecule donates a lone pair of electrons to the aluminium ion. This results in the formation of a coordinate covalent bond between the aluminium ion and the ammonia molecule.
A Bronsted-Lowry acid is a substance that donates a proton (H+) to another substance. An Arrhenius acid is a substance that increases the concentration of hydrogen ions (H+) in solution.
A Lewis base is a chemical species that donates an electron pair to form a Lewis adduct. Lewis bases are typically electron-rich species, such as anions and molecules with lone pairs of electrons.