A house-shaped figure (a rectangle topped by an isosceles triangle, with the triangle's apex directly above the rectangle's center) is shown. How many lines of symmetry does this composite figure have?
AExactly 4 (matching a square's symmetry)
BExactly 2 (one vertical, one horizontal)
C0 (composite figures combining two different shape types never have symmetry)
DExactly 1 (the single vertical line through the center)
Explanation
The rectangle alone would have 2 lines of symmetry (vertical and horizontal), and the isosceles triangle alone has 1 (vertical). But the COMBINED figure only shares the symmetry present in BOTH parts — a horizontal flip would not map the peaked roof onto the flat rectangle bottom, so only the vertical line through the shared center survives as a line of symmetry for the whole figure.
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