The word "discriminatory" in the text means prejudicial. Discriminatory refers to treating certain groups or individuals unfairly or unfavorably based on characteristics such as race, gender, or nationality. In this context, discriminatory immigration laws prevented Mabel Ping-Hua Lee from becoming a U.S. citizen despite her achievements and contributions, highlighting the unfair treatment she faced due to her Chinese heritage. So, the correct meaning of "discriminatory" in this context is prejudicial because it indicates bias or unfairness based on specific characteristics.