【单选题】
What is a primary partner benefit of selling services?（）
A、easier customer sales cycle
B、increased margins
C、fewer customer call backs
D、available financing options
查看正确答案
A、The primary line module is inactive for five minutes and then becomes active. B、The primary line module is in standby mode，while the spare line module remains active. C、The primary line module becomes active immediately and the spare line module becomes inactive. D、The primary and spare line modules are active for five minutes，after which time the spare line module becomes inactive.
