Answer:
The answer to your question is A. In my community, it's a law that all dogs out on walks must be on leashes, so most dogs I see on walks today will be on leashes.
Step-by-step explanation:
In the case of the letter A, the speaker arrives concludes that all dogs are on leash, because he knows of the existence of a law that implies that all dogs on walks should be on leash.
I hope this helps and have a great day!