Question: when did gender testing of female olympic athletes begin
[{'answer': '1968', 'provenance': [{'wikipedia_id': '844733', 'title': 'Sex verification in sports', 'start_paragraph_id': 2, 'start_character': 541, 'end_paragraph_id': 2, 'end_character': 545, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '844733', 'title': 'Sex verification in sports', 'start_paragraph_id': 2, 'start_character': 95, 'end_paragraph_id': 2, 'end_character': 549, 'bleu_score': 0.775502382152184, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12047863699162281343}, 'section': 'Section::::Abstract.'}]}]