Group the given figures into three separate classes using each figure only once.

Concept: In figure-classification questions, figures are sorted into groups based on a shared structural property, such as an identical internal mark, a smaller copy of the same shape nested and touching inside it, or the same pattern of dividing lines, rather than by number of sides or overall size. Each figure is used in exactly one group.

1. Figures 1 and 3 each contain a single V-shaped (chevron) mark placed inside their outer shape (a circle and a square respectively), touching the upper boundary.

2. Figures 2, 4, and 5 each contain a smaller copy of the same outer shape nested inside it and touching it: a smaller circle inside a circle, a smaller square inside a square, and a smaller triangle inside a triangle.

3. Figures 6 and 7 each have their outer shape divided into four equal parts by two mutually perpendicular straight lines: a plus-shaped division inside the circle and an X-shaped (diagonal) division inside the square.

Cross-check: Every figure from 1 to 7 appears in exactly one of the three groups: {1,3}, {2,4,5}, {6,7}. That is 2 + 3 + 2 = 7 figures, with no figure repeated or omitted, matching the grouping 1,3 ; 2,4,5 ; 6,7.

This matches the grouping 1,3 ; 2,4,5 ; 6,7.