The correct answers are: the setting of the story, the central conflict in the story, and the ending of the story.
When writing a summary it is necessary to include some information about the setting, particularly the main characters. This is because the reader has to know the starting point of the story. The central conflict and how it evolves up to the ending are also essential, since they tell what the story is actually about. The ending should be included because it is part of the summary, since it tells the outcome and final message.
The other options could be included but it depends on their relevance within the story, that is they are not essential to every summary