Lactase, the Enzyme Responsible for Breaking Lactose into Its Monomers $\beta$

Lactase, the enzyme responsible for breaking lactose into its monomers, is a(n) _____ enzyme.

A) $\beta$ -galactosidase
B) $\alpha$ -amylase
C) $\alpha$ -glycosidase
D) $\beta$ -glycosyltransferase
E) none of the above