Final answer:
The principle of design referred to in Egon Schiele's Portrait of a Woman (1910) is balance.
Step-by-step explanation:
When we look at the relative size of the woman's face compared to her hand on her chin in Egon Schiele's Portrait of a Woman (1910), the principle of design that we refer to is balance. Balance refers to the distribution of visual weights in a composition, and in this case, the size of the woman's face and hand creates a harmonious equilibrium.
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