Final answer:
In Genesis 3:15, the enmity is between the serpent and the woman and her offspring. It symbolizes the ongoing struggle between good and evil, with the eventual victory of humanity over evil.
Step-by-step explanation:
In Genesis 3:15, God says, "I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel." The subject of this enmity is between the serpent symbolizing evil and the woman and her offspring representing humanity. The phrase "he will crush your head" refers to the future victory of humanity over evil, while "you will strike his heel" suggests that evil will still cause harm but will ultimately be defeated.