Dear teachers,

It is life. The stronger devour the weaker even among human beings. Dog kills snake. Snake kills birds. Birds kill the butterflies. Man conquers all. Man, too, kills for sport.

The boy thought that the sronger devour the weker and man conquer for__________.

a. fun b. survival
The key is "a". I get confused. We have to choose "a" because the boy doesn't say man conquers for survival. Is that right? But why does he say "Man, too, kills for sport"? And what does this "Man conquers all" for? Doesn't it mean "for survival"?

Looking forward to hearing from you.
Thank you in advance.

Jiang