Both bus and tree topologies are characterized by the use of multipoint(1)．For the bus,all stations attach,through appropriate hardware(2) known as a tap,directly to a linear transmission medium, or bus. Full-duplex operation between the station and the tap allows data to be transmitted onto the bus and received from the(3).Atransmission from any station propagates the length of the medium in both directions and can be received by all other(4).At each end ofthe bus is a(5),which absorbs any signal, removing it from the bus．

空白（1）处应选择（）

A.medium

B.connection

C.token

D.resource

患者女，53岁。发现颈部肿物2周，无疼痛，查体甲状腺右叶肿物，质硬，高低不平，甲状腺同位素¹³¹碘扫描，显示为冷结节。治疗应首选（）

A.中医辨证论治

B.针灸治疗

C.外用油膏

D.手术治疗

E.冷冻治疗