Answer:
A. Gatsby's desire to regain what he once had.
Step-by-step explanation:
The green light in The Great Gatsby refers to a light at the end of Daisy's East Egg dock, which can be seen from Gatsby's home. This light has a symbolic meaning in the novel, as it represents Gatsby's hopes and dreams to regain the future that he once had. As the light is equivalent to Daisy, we also learn that Gatsby associates all these dreams with Daisy, and the possibility of being back with her again.