Explanation

B is correct because Kylie Jenner was listed as the world's youngest self-made billionaire in 2019. A is incorrect because Jeff Bezos was not the youngest self-made billionaire according to that list. C is incorrect because Jim Ratcliffe was not the youngest self-made billionaire according to that list. D is incorrect because Mark Zuckerberg was not the youngest self-made billionaire according to that list.