The correct answer is:
On the other hand.
"He looked forward to visiting with old friends. Greta, on the other hand, dreaded seeing her old boyfriend."
This phrase is showing Greta and Fred are having different feelings in that moment, creating a contrast between both of them.
One of them is that Gatsby to war when he single handedly defeated the German army
another one is that all of his family was dead and that he had inherited all of his money from that family
Answer Literal
Example:
"Techniacally it doesn't actually fly, it's just a metal plane model."
