Question: who plays troy bolton in high school musical
[{'answer': 'Zac Efron', 'provenance': [{'wikipedia_id': '22857478', 'title': 'List of High School Musical characters', 'start_paragraph_id': 6, 'start_character': 47, 'end_paragraph_id': 6, 'end_character': 56, 'bleu_score': 1.0, 'section': 'Section::::Main cast.:Troy Bolton.\n'}]}]