（）是保证人和债权人约定当债务人不履行债务时，保证人按照约定履行债务或者承担债务的行为。 ["A.保证 ","B.抵押 ","C.质押 ","D.留置"]
物体的灰面部分因受光不足显的明度微弱，色彩以（）为主，同时受上下左右不同方向的环境色的影响。 ["光源色","反光","环境色","固有色"]
在平静状态下，关于胎动计数下列描述正确的是（） ["12h内胎动计数不得小于15次","胎动2次\/h","胎动2次\/h","嘱孕妇每次早晨各数1h胎动","是孕妇自我检测胎儿宫内情况的一种重要手段"]
同感反应的要领为 （） ["心理位置互换","倾听整理","正确反应","建立友谊"]
Refer to the exhibit. HSRP has been configured and Link A is the primary route to router R4. When Link A fails， router R2 （Link B） becomes the active router. Which router will assume the active role when Link A becomes operational again？" （） [" The primary router R1 will reassume the active role when it comes back online."," The standby router R2 will remain active and will forward the active role to router R1 only in the event of its own failure."," The standby router R2 will remain active and will forward the active role to router R1 only in the event of Link B failure."," The third member of the HSRP group， router R3， will take over the active role only in event of router R2 failure."]
生态位
