

................... is called erosion
A. The wearing away of land
B. When land wears away
C. Land that wears away
D. Wearing away land
( tại sao ko chọn B ạ ??? )
A. The wearing away of land
B. When land wears away
C. Land that wears away
D. Wearing away land
( tại sao ko chọn B ạ ??? )