Question: who was the first leader of the universities mission to central africa
[{'answer': 'Charles Mackenzie', 'provenance': [{'wikipedia_id': '23666702', 'title': "Universities' Mission to Central Africa", 'start_paragraph_id': 5, 'start_character': 89, 'end_paragraph_id': 5, 'end_character': 106, 'bleu_score': 1.0, 'section': 'Section::::First mission.\n'}]}, {'provenance': [{'wikipedia_id': '23666702', 'title': "Universities' Mission to Central Africa", 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 907, 'bleu_score': 0.9868845362499331, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5728011753389449840}, 'section': 'Section::::First mission.\n'}]}]