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)
Theme I believe I haven't done that for awhile
The highlighted sentence that also has a box around it is the making of a strong thesis statement