Question: who are the scientists credited with introducing the phenomena known as radioactivity
[{'answer': 'Marie Skłodowska - Curie', 'provenance': [{'wikipedia_id': '1416046', 'title': 'History of chemistry', 'start_paragraph_id': 122, 'start_character': 0, 'end_paragraph_id': 122, 'end_character': 26, 'bleu_score': 1.0, 'section': 'Section::::19th century.:Late 19th century.:Marie and Pierre Curie.\n'}]}, {'provenance': [{'wikipedia_id': '1416046', 'title': 'History of chemistry', 'start_paragraph_id': 122, 'start_character': 0, 'end_paragraph_id': 122, 'end_character': 1134, 'bleu_score': 0.9758151891653221, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1779160410497992136}, 'section': 'Section::::19th century.:Late 19th century.:Marie and Pierre Curie.\n'}]}]