Final answer:
The quote that best supports the American Dream and the green light symbol in 'The Great Gatsby' is "Gatsby believed in the green light, the orgastic future that year by year recedes before us." This line encapsulates the aspirations of the American Dream and the continuous yet futile pursuit of an elusive future.
Step-by-step explanation:
The quote that best supports the theme of the American Dream and the symbol of the green light in "The Great Gatsby" is option a) "Gatsby believed in the green light, the orgastic future that year by year recedes before us." This line encapsulates the central theme of aspiration and the perpetual pursuit of a future just out of reach, which is intrinsic to the concept of the American Dream. The green light, representing both Gatsby's unattainable desires and the broader pursuit of happiness, becomes a powerful symbol of this ceaseless quest.
Option b) "His dream must have seemed so close that he could hardly fail to grasp it." and option c) "So we beat on, boats against the current, borne back ceaselessly into the past." also strongly reflect on the unfulfilled desires and the inherent struggle in chasing dreams, akin to the American Dream. However, it is option a) that directly correlates the green light with the perennial chase for a promising future, thus highlighting both these pivotal themes of F. Scott Fitzgerald's work.