Answer:
B. The hikers noticed the bears.
Step-by-step explanation:
so the meaning of the original passive sentence is that the BEARS were noticed by the HIKERS, not the other way around. choice B is correct because the HIKERS are still noticing the BEARS. it can't be A or D because the bears aren't supposed to be noticing the hikers, and C is just like the original sentence but written with "near" instead of "by"