The stage directions affect how the audience instruct in the text of a play, especially one indicating the movement, position, or tone of an actor, or the sound effects and lighting.
I'd say I guess C. asking the advice of a reference librarian
A.argue for or against the limitation of speed limits
I believe the correct term to fill in the blank would be erosion. It is the process in which materials on or near Earth's surface break down and change. It is a natural process by which soil is loosened from the surface of the Earth. Hope this helps.