Question: the nature of c-sn bond in alkyl tin is
[{'answer': 'invariably tetrahedral', 'provenance': [{'wikipedia_id': '1867619', 'title': 'Organotin chemistry', 'start_paragraph_id': 5, 'start_character': 32, 'end_paragraph_id': 5, 'end_character': 54, 'bleu_score': 1.0, 'section': 'Section::::Structure of organotin compounds.:Organic derivatives of tin(IV).\n'}]}, {'provenance': [{'wikipedia_id': '1867619', 'title': 'Organotin chemistry', 'start_paragraph_id': 5, 'start_character': 0, 'end_paragraph_id': 5, 'end_character': 135, 'bleu_score': 0.8852140475440831, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12258918535825771310}, 'section': 'Section::::Structure of organotin compounds.:Organic derivatives of tin(IV).\n'}]}]