Answer:
Antigone's decision to defy Creon's orders and bury her brother is part of rising action of the play.
Step-by-step explanation:
"Antigone" is third of Sophocles' three Theban plays/tragedies.
Antigone's decision to defy Creon's orders and bury her brother is an event which leads the plot to its climax. It is an event which creates suspense in the story. These reasons make Antigone's decision a part of the rising action.
Components of a typical plot are,
Exposition: It is a sort of introduction to play's main characters, setting, conflicts and events. In some plays it is in the form of Prologue, while in some others it is Act 1. Exposition is followed by rising action.
Rising Action: It is collection of all conflicts, tensions and events which are the driving force of the story.
Climax: It is the peak of the story, where reader's suspense is at its highest point. There may be more than one (mini) climaxes in some literary works as well.
Falling Action: In this part of the plot the conflicts and tension start to resolve.
Denouement: It is the end of the story - happy, tragic, neutral etc.
These parts do not have sharp boundaries, moreover various literary works may have some of the parts very short, and some other parts very long.
Second and third options are part of falling action, while fourth option is exposition.