what categorizes an office as large?

In the Cisco branch office design, what categorizes an office as large?

A.
between 50 and 100 users and a single-tier design

B.
between 100 and 200 users and a three-tier design

C.
between 50 and 100 users and a three-tier design

D.
over 200 users and a two-tier design

E.
between 100 and 200 users and a two-tier design