Final answer:
The collar marking that represents Apollo is the sunburst, which symbolizes his role as the god of the sun in Greek mythology.
Step-by-step explanation:
The collar marking that represents Apollo is a) Sunburst. Apollo is a significant figure in Greek mythology and one of the Olympian deities. He is associated with many aspects including the sun, music, poetry, and more. The sunburst is a symbol representative of his role as the god of the sun. A lyre is representative of his association with music, the laurel wreath is associated with victory, which can also be linked to him through the Pythian Games, and the bow and arrow represent his role as the god of archery.