Final answer:
The advance in the pedimental sculptures of the Temple option (a) of Aphaia on Aegina is the introduction of a unified theme and consistent scale, which exhibited a more developed sense of spatial organization and naturalism in the figures.
Step-by-step explanation:
The advance evident in the pedimental sculptures of the Temple of Aphaia on Aegina pertains to B. Introduction of unified theme and consistent scale. Unlike earlier pedimental sculptures that did not always maintain a consistent scale across figures, the Temple of Aphaia exhibits a developed sense of spatial organization, with figures scaled to fit the pedimental space effectively, reflecting a more advanced stage in Greek sculpture.
Focusing on the west pediment, the dying warrior's portrayal offers an example of increased naturalism compared to previous works such as those seen at the Temple of Artemis at Corfu. This advancing naturalism is characterized by a depiction of human musculature and more lifelike poses, despite the stylized hair of the figures.
Moreover, the placement and scaling of figures like Zeus fighting a Titan and the slaying of Priam by Neoptolemos illustrate a conscious effort to create a more cohesive and intelligible narrative across the entire pediment.
As the figures are made to the same scale, attention is also given to the treatment of the Goddesses' drapery, which becomes fluid and reveals the bodily forms beneath, thereby presenting a unified and well-composed scene within the architectural constraints of the pediment.