Answer:
D All of the above
Step-by-step explanation:
Like our bones, bones in fish can provide general protection and support to their body.
(Fun fact, jellyfish do not have bones, so when they are out of the water, they loses their bell shape structure and looks more like a flat piece of jelly. But fish tends to look the same when it is in water and out of water.)
The bone is also where the muscles will attach to, which allows for movement.
(Imagine our fingers, the muscles in our fingers are attached to our bones, which allows us to do things like typing.)
Bones can also protect the fish's brain.
(Brain can be very fragile and soft, so having a hard structure around it can protect the brain. It's kind of similar to protecting the liquid egg in an egg shell.)