Final answer:
Mesopotamian architecture is best described by statement D, which mentions the use of glazed and baked mud bricks for surfacing important buildings.
Step-by-step explanation:
Out of the options provided, the statement that describes Mesopotamian architecture is D, 'Important buildings are surfaced with glazed and baked mud bricks.' Mesopotamian architecture is notable for the usage of sun-baked bricks, and for important structures like temples and palaces, glazed and baked bricks were used. Moreover, the walls of these significant structures were sometimes adorned with vibrant colors, enamelled tiles, and the interiors could contain frescoes. While options A and B might describe aspects of Mesopotamian art and smaller-scale architecture, such as domestic buildings, option C is incorrect as marble was not commonly used due to the lack of stone in Mesopotamia.