Inadequate transport network and energy constraints are practica

Inadequate transport network and energy constraints are practical bottlenecks in our economy.
A、advantages
B、faults
C、barriers
D、bottlers
【正确答案】：C
【题目解析】：bottlenecks意为“瓶颈”；advantages优势；fault故障；barriers障碍；bottler瓶子；故选C。