Question: Boots that rise to the knee and were originally made of leather, can be made of a synthetic rubber that exhibits good chemical stability, and is produced by the polymerization of what?
{'answer': 'chloroprene', 'supporting_facts': [['Knee-high boot', 0], ['Knee-high boot', 2], ['Neoprene', 0], ['Neoprene', 1]]}