Question: who has been on law and order svu the longest
[{'answer': 'Mariska Hargitay', 'provenance': [{'wikipedia_id': '197060', 'title': 'Law & Order: Special Victims Unit', 'start_paragraph_id': 1, 'start_character': 170, 'end_paragraph_id': 1, 'end_character': 186, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]