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
