A/B选项的意思是“sound be prevented from dissipating”，这在逻辑意义上错误，不是sound be prevented from dissipating，而是the energy of sound be prevented from dissipating。排除A/B。E选项表达的是sound prevent its acoustic energy from dissipating，逻辑意思错误，而应是boundaries prevent its acoustic energy from dissipating。排除E。C/D选项是独立主格结构with + 名词 + done + 介词，此处省略with。D选项being多余，且as a result of用法出错，即不是boundaries的结果保护了acoustic energy。排除D。正确选项C。