I believe that (A) allowed for function, historical significance, and aesthetics to all be important.
Function: The statues also function as the pillars of the building to hold the building up
Historical significance: The statues look to me to be carved with the impression of a certain ruler, and have historical significance of what the ruler have done carved on the bottom part of his 'clothing'.
Aesthetics: As this is a masterpiece, and uses art to express the history, Aesthetics is also used.
hope this helps
