She wanted to choose complementary colors.
The question in " (I’m Overwhelmed) Vocab Progress Quiz #17a" asks us to select between “compatible” and “contrasting”.
This is a hard one since the world colours is used. Complementary colours are actually contrasting colors!
If you look at a color wheel, the opposing sides are actually compatible (look pleasant) but are contrasting (since they are on opposite sides of the wheel). Complementary, supplementary, and contrasting colors are all the same.