Question: where did a massacre occur on march 16 1968
[{'answer': 'South Vietnam', 'provenance': [{'wikipedia_id': '68292', 'title': 'My Lai Massacre', 'start_paragraph_id': 1, 'start_character': 68, 'end_paragraph_id': 1, 'end_character': 81, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '68292', 'title': 'My Lai Massacre', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 763, 'bleu_score': 0.814337582539934, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14681600067730187905}, 'section': 'Section::::Abstract.'}]}]