How is the underlined portion of this excerpt best characterized?

Read the excerpt from "black hole beginnings." as the star material gathers, its inward pressure grows. the nuclei respond by zipping and zooming faster and faster, veering away from each other all the while. which statement best describes the cause and effect relationship(s) in this excerpt? 1.one cause (star material gathers) leads to two effects (inward pressure grows and nuclei zip and zoom). 2.one cause (star material gathers) leads to one effect (inward pressure grows), which becomes a cause of two additional effects (nuclei zip and zoom, and nuclei veer away from each other). 3.one effect (nuclei zip and zoom) is the result of two causes (star material gathers and inward pressure grows). 4.two effects (inward pressure grows and nuclei veer away from each other) are the result of two causes (star material gathers and nuclei zip and zoom).