[单选] For a lightweight access point to participate in aggressive load balancing， it must have heard the client for how many seconds？（）
A . 15 B . 10 C . 1 D . 5
感觉过敏
离心泵，柱塞泵的操作步骤？
恒压源的性质是什么？
充气效率
罪犯依法必须履行的义务主要有（） 三项。 四项。 五项。 六项。
For a lightweight access point to participate in aggressive load balancing， it must have heard the client for how many seconds？（）
