Question: name the type of mutation that does not effect protein synthesis
[{'answer': 'Silent mutations', 'provenance': [{'wikipedia_id': '19702', 'title': 'Mutation', 'start_paragraph_id': 94, 'start_character': 399, 'end_paragraph_id': 94, 'end_character': 415, 'bleu_score': 1.0, 'section': 'Section::::Classification of types.:By impact on protein sequence.\n'}]}, {'answer': 'silent substitutions'}]