GRE Text Completion: Fundamental 24 Sets-GRE填空基础24套 - LY6R0N9SX1N1066D!

The Amazon rain forest remained (i)____________ for years because its soils were unsuitable for agriculture and because endemic diseases such as malaria and yellow fever (ii)____________ most settlers. A. pristine B. attracted C. luminous D. thwarted E. cultivated F. exposed