Number two i dont get it

However, the idea of real-life people living in what would become the united states for thousands of years before columbus ever left spain never dawned on me. what would be the best way to revise this sentence for greater clarity? a) however, the fact that columbus left spain thousands of years after people settled what would become the united states never dawned on me. b) it never dawned on me, however, the idea of real-life people living in what would become the united states for thousands of years before columbus ever left spain. c) however, the fact that people were already living in what would become the united states for thousands of years before columbus ever left spain never dawned on me. d) however, the idea never dawned on me that long before columbus ever left spain, real-life people lived for thousands of years in what would become the united states.

My cat and my dog like best friends

Based on the cause-and-effect relationship in this sentence, what is the meaning of the word revert? the brownies kali made using a new recipe were too dry, so she reverted to her original recipe. a) to alter or change completely; revise b) to dispose of or remove; to throw away c) to prepare for something; assemble or make d) to go back to a previous state or practice