qnli question: what group's productions for Mel and Kim added elements of house to the europop sound? sentence: Stock Aitken Waterman's productions for Mel and Kim, including the number-one hit "Respectable", added elements of house to their previous Europop sound, and session group Mirage scored top-ten hits with "Jack Mix II" and "Jack Mix IV", medleys of previous electro and Europop hits rearranged in a house style.