Each guide was helpful, but we forgot to thank them.
You should use the plural pronoun, because we don't know whether the guides were only males, or females, or whether there were both sexes.
The simple subject is obviously kittens.....
It can identify(if you know who is narrating) to tell you if you are in third person or first person or it can identify who is the narrator if you know what person you are writing in. The second person should never be used in a narrative essay. That would be informal and incorrect. You can also identify when it is taking place in some cases............. I don't know if this helped but I tried
The answer is B, sorry if i’m wrong but before willow it says “young” ..