Which of these was a favored medium among artists who painted in the International Gothic style?

Among the options provided, oil paints were a favored medium among artists who painted in the International Gothic style. While water-based tints were also used, especially in earlier periods, the use of oil paints became more prominent during the late Gothic and into the Renaissance, allowing for greater detail and richer colors. Mosaic tiles are not typically associated with the International Gothic style in painting.