问题详情

What point does the professor make when he mentions that good topsoil takes thousands of years to form？

A．It takes a long time to ruin good topsoil.

B．It was wrong to believe that land could not be damaged.

C．Farmers should not have moved on to other places.

D．Plowing the land creates good topsoil faster than natural processes do.

此题为多项选择题。请帮忙给出正确答案和分析，谢谢！