Conflict is not one of the main five of a plot
The answer would be (A) again because in a essay you are stating your points and you have a structure on how to do it and it must be consistent throughout the whole essay or its going to be choppy and you wont get a good grade. hopefully that made sense. The other answers wouldn't make sense. So go with (A)
Is there a picture to help me understand what ur doing
C) I would say. You can learn many things from rollercoasters, like how much mass they can hold. The distance they go in a daily trip. Rollercoasters can be of use for science for a fun learning experience!