Paul has two label-printing machines. Each machine can print 30 labels per minute. On day 1, only the first machine was used, and it printed 90 labels. On the following day, the first machine printed for x minutes and the second machine printed for y minutes. Which expression shows the total number of labels printed by both machines during these two days? A) 120x + 30y B) 90 + 30x + 30y C) 30 + 90x + y D) 90x + 60y