Final answer:
Margaret should use the trompe-l'oeil technique to create a three-dimensional illusion of the inside of the Sun, making use of light, shadow, and perspective.
Step-by-step explanation:
Margaret wants to present a close-up view of the inside of the Sun as though through a cut-away portion of the Sun's surface. To achieve this effect in her painting, she should use a technique that allows for the creation of depth and the illusion of a three-dimensional space. One such approach involves the use of light and shadow, as well as perspective techniques, to render the illusion of space. Trompe-l'oeil, a French term which means 'deceive the eye', is one technique that could serve this purpose by creating a highly realistic image that can trick the viewer's sense of depth perception. Trompe-l'oeil intricately plays with light, shadow, and perspective to make a two-dimensional painted surface appear three-dimensional.