请写出5种宝石学中的特殊光学现象，并分别解释其形成原因。
If all OSPF routers in a single area are configured with the same priority value,what value dose a router use for the ODPF router ID in the absence of a loopback interface?（） [" the IP address of the first Fast Ethernet interface"," the IP address of the console management interface"," the highest IP address among its active interfaces"," the lowest IP address among its active interfaces"," the priority value until a loopback interface is configured"]
岩石圈由（）三类岩石构成。 ["沉积岩","玄武岩","岩浆岩","变质岩"]
《源氏物语》的作者是？（） ["贵族妇女","农村妇女","皇室妇女","艺妓"]
可保风险的特性是：（） ["风险不是投机性的","风险必须具有不确定性","风险必须是少量标的均有遭受损失的可能性","风险可能导致较大损失","风险在合同期内预期的损失是可计算的"]
语言清晰度
