Which statement is true for glycogen phosphorylase b$?$

Select one:

a$.$

It is regulated both allosterically and via covalent modification.

b$.$

It is an important blood glucose sensor in myocytes.

c$.$

It catalyzes a phosphorolytic cleavage of$($$16)$glycosidic bonds.

d$.$

It catalyzes a hydrolytic cleavage of$($$14)$glycosidic bonds.

e$.$

It uses UDP$-$glucose as a substrate.