Select the alternative which represents three out of the five alternative…

In a figure-assembly question, three of the five given pieces must combine edge-to-edge — no gaps and no overlaps — so that their outlines together retrace the target shape's outer boundary as well as any internal lines dividing it into regions. A piece can occupy a region only if its own edges match both the boundary segment it covers and the touching edge of each neighbouring piece.

1. The target diagram's square outline is broken by internal lines into three sections that must each be filled by one of the candidate figures, so the three chosen figures need matching edges wherever they touch each other and wherever they meet the square's own border.

2. Among the five figures, (2), (3), and (4) have edges whose lengths and slant angles line up with one another in sequence: figure (2)'s slanted edge meets figure (3)'s matching angled edge, and figure (3)'s remaining angled edge meets figure (4)'s edge.

3. Assembled in that order, the three outlines together retrace the square's full outer boundary and its internal dividing lines, with every touching edge flush — so figures (2), (3), and (4) complete the square.

• Figure (1)'s overall shape closely resembles figure (2)'s, but its lower edge follows a different angle and length, so once placed next to the piece it should adjoin, the edges no longer meet flush — leaving a gap or overlap instead of a clean line.

• Figure (5) is a larger, more irregularly angled shape than any of the three sections in the target square, so wherever it is placed, part of it runs past the square's own border.

So the correct group of three is figures (2), (3), and (4) — option "234".