单选题A second network card in a server that activates if the primary card fails is an example of which of the following network performance optimization？（）A Load balancingB QoSC High availabilityD Fault tolerance
题目
单选题
A second network card in a server that activates if the primary card fails is an example of which of the following network performance optimization？（）
A
Load balancing
B
QoS
C
High availability
D
Fault tolerance