When can we exercice an option?
Owners of American-style options may exercise at any time before the   option expires, while owners of European-style options may exercise   only at expiration. Read more: American Vs. European Options
Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
When can we exercice an option?

### Response:
Owners of American-style options may exercise at any time before the   option expires, while owners of European-style options may exercise   only at expiration. Read more: American Vs. European Options