Table schema:
CREATE TABLE table_name_75 (national_final_main_host VARCHAR, venue VARCHAR, selection_show VARCHAR)

Question: What is the name of the national final main host at BBC Television Centre, and the selection show was Eurovision: Your Country Needs You?
SQL: SELECT national_final_main_host FROM table_name_75 WHERE venue = "bbc television centre" AND selection_show = "eurovision: your country needs you"