。
She fulfilled her duty.
Literal
She [topic-は] duty [object-を] fulfilled.
義務を果たす is a stable collocation — the standard pairing for 'fulfill a duty, discharge an obligation.' 果たす ('to accomplish, to fulfill, to carry out') often pairs with abstract nouns of role or responsibility: 役割を果たす ('play a role, fulfill a function'), 約束を果たす ('keep a promise'), 期待を果たす ('live up to expectations'). The verb implies completion against an external standard rather than mere doing.