Final answer:
The torch is one of Demeter's symbols because it represents her search for her daughter, Persephone, who was kidnapped by Hades. The torch also symbolizes the nocturnal setting of the initiation in the Mysteries, a religious festival dedicated to Demeter and Persephone.
Step-by-step explanation:
In Greek mythology, Demeter is the goddess of agriculture and fertility. The torch is one of her symbols because it represents her search for her daughter, Persephone, who was kidnapped by Hades. Demeter wandered the earth with a torch in her hand, looking for her daughter. The torch also symbolizes the nocturnal setting of the initiation in the Mysteries, a religious festival dedicated to Demeter and Persephone.