1. A display control apparatus comprising: calculating means for calculating the degree of similarity of each of a plurality of second images to a selected first image; display control means for controlling displaying of the second images in the order of similarity; and selecting means for selecting, in response to an instruction from a user, one second image from among the plurality of second images displayed in the order of similarity, in response to the selection of the one second image, the display control means controlling the displaying of the second image and a third image belonging to the same group as the selected second image so that the third image and the second image are displayed in accordance with a predetermined order in the group.