A series of figures are given which can be grouped into classes. Select the group into which the figures can be classified from the given responses.

• [1, 7; 2, 4; 3, 5; 6, 8]
• [1, 4; 2, 7; 3, 5; 6, 8]
• [1, 3; 2, 7; 6, 8; 4, 5]
• [1, 4; 3, 6; 3, 5; 7, 8]