题目
How does an early-warning system help us maintain the ecological balance?A. By getting illegal practices under control.B. By stopping us from killing large predators.C. By bringing the broken-down ecosystems back to normal.D. By signaling the urgent need for taking preventive action.
How does an early-warning system help us maintain the ecological balance?
A. By getting illegal practices under control.
B. By stopping us from killing large predators.
C. By bringing the broken-down ecosystems back to normal.
D. By signaling the urgent need for taking preventive action.
题目解答
答案
D. By signaling the urgent need for taking preventive action.