Which Stylistic Characteristic Distinguishes Fourteenth-Century Figure Painting in Siena from That

Which stylistic characteristic distinguishes fourteenth-century figure painting in Siena from that produced in Florence?

A) the use of modeling to suggest three-dimensional forms
B) the placement of figures in naturalistic and architectural settings
C) an emphasis on jewel-like coloring and elegantly posed forms
D) the use of tempera paint on small-paneled altarpieces