【单选题】
Acknowldgement, Sequencing, and Flow control are characteristics of which OSI layer?（）
A、Layer 2
B、Layer 3
C、Layer 4
D、Layer 5
E、Layer 6
F、Layer 7
查看正确答案
A、Layer 2 B、Layer 3 C、Layer 4 D、Layer 5 E、Layer 6 F、Layer 7
