Which best describes the big bang theory? a. matter was compressed into a single point and then exploded outward to form the universe. b. a black hole exploded, creating stars. c. stars burn off their fuel, expand, and shed their shells.

A)before the bigbang.there was alot of nothing packed into nothing.matter and time.sapce and stars did not exist till then scientisys havent foind a way yet to know wjat was tjere before the big bang.so we cannot sah stars exploded or a black hole died.but whay we can say is thatba very dense pinprick.very very very very very dense pinprick of nothing ness expanded.and created matter as it heated up

The troposphere gets warmer as altitude increases.