I want to say it will be first-person. Third-person is an outside voice, someone that is not a character in the plot. It seems as if the narrator is talking about himself, which is why I deduce it to being a first-person point of view.
B: The emergency <em>lights</em> atop the fire trucks <em>were</em> flashing. Lights is your noun and were acts like your verb.
for A it should be: The exhibits on the lower level are not currently open to the public.
for C it should be: That man, wearing sunglasses, seems to be an undercover police officer.
for D it should be: Perry, like his younger sister Pauline, writes very neatly.
Hopefully this helped and good luck.
If you are going to write a short story, you don't need to make things up entirely.
You should always use as much creativity as you can, but you can also take elements from real life and incorporate it in your story.
Two things. Wave in water or wave with a hand.