Three of them. 인생 and 삶 have almost same meaning. It means lifetime. Only thing that differ each other is that 인생 covers only human life and 삶 covers all the creatures' life. U can use those two when u wanna say like this 'In your life, Friendship is very important.' However 생명 means something u can lose when u die. so u can use it when u wanna say like this 'ten lives were lost'