Question: who controlled or ordered the viet cong in combat
[{'answer': 'Nguyễn Hữu Xuyến'}, {'answer': 'Trần Văn Trà', 'provenance': [{'wikipedia_id': '68286', 'title': 'Viet Cong', 'start_paragraph_id': 27, 'start_character': 211, 'end_paragraph_id': 27, 'end_character': 223, 'bleu_score': 1.0, 'section': 'Section::::History.:Tet Offensive.\n'}]}, {'answer': 'Hoàng Văn Thái'}]