- Wasp 's stinger contains poison
- Poison causes harm to living things
- Therefore, a wasp's stinger can be used to cause harm to living things

- A wasp's stinger can be used to cause harm to living things
- Harming is a kind of defense
- Hence, a stinger is used for defense by a wasp

Therefore, a stinger is used for defense by a wasp
[Question]A wasp uses poison in a stinger to
[Context]- Wasp 's stinger contains poison 
- Harming is a kind of defense 
- Poison causes harm to living things