社会保障的内容主要包括三大部分（）A、社会救助B、社会保险C、社会福利D、家庭服务E

To keep safe is very important. When you are alone at home, you should ______ to protect yourself.

①have a list of phone numbers to call for help, such as 110,119 and 120

②play computer games while boiling some water

③keep the door locked

④pay attention to the gas, water and electricity

⑤let anybody in immediately when you hear the doorbell       [ ]

A. ①④⑤                      

B. ②③⑤                  

C. ①③④

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