Question: who is the pioneer in psychology responsible for studying classical conditioning
[{'answer': 'Ivan Pavlov', 'provenance': [{'wikipedia_id': '188540', 'title': 'Classical conditioning', 'start_paragraph_id': 3, 'start_character': 54, 'end_paragraph_id': 3, 'end_character': 65, 'bleu_score': 1.0, 'section': 'Section::::Overview.\n'}]}]