Who is the mother of Achilles?

The correct answer is that Thetis is the mother of Achilles. In Greek mythology, Thetis is a sea nymph and goddess who is well-known for her beauty and is one of the Nereids. She plays a significant role in the mythological narrative surrounding Achilles, particularly in Homer's "Iliad".

Thetis is notable for her protective nature towards her son; she attempts to make Achilles invulnerable by dipping him in the River Styx, which grants him near invincibility, except for the heel by which she held him. This detail about Achilles' heel has led to the term "Achilles' heel," referring to a singular vulnerability despite overall strength.

The other figures mentioned do not have a maternal relationship with Achilles. Hera is known as the queen of the gods and has no direct connection to Achilles as his mother. Demeter is the goddess of the harvest and agriculture, while Aphrodite is the goddess of love and beauty, neither of which are related to Achilles in a maternal sense. Understanding the role of Thetis in Achilles' life helps to illuminate the themes of fate, protection, and heroism that permeate Greek mythology.