Passage: Six months later, Seth and Summer fall into a rut after the earthquake, and spend hours watching Briefcase or No Briefcase (a television game show take-off of Deal or No Deal). Seth tells her that she must join GEORGE, and they'll always be together. Summer leaves Seth to help the environment and they say farewell. Summer attends protests and works to save the environment and educate students on environmental issues for a year. She appears in newspaper articles as an environmentalist. In a flash-forward sequence, Summer ends up marrying Seth.

Question: Based on this passage, who does summer end up with in the oc?
Steam of consciousness below:
The important part for answering this question is: In a flash-forward sequence, Summer ends up marrying Seth.
So, the answer is Seth.