Ecological succession refers to the regular replacement process of biological communities in the same area, which can be divided into primary succession and secondary succession. The succession started on the bare land where there has never been vegetation in the past, or the original vegetation has been completely destroyed, and the soil under the original vegetation no longer exists is called primary succession; The succession that begins where the original vegetation has been destroyed but the soil and plant reproductive body are still maintained is called secondary succession. The biological community in which secondary succession occurs tends to return to the form before destruction.
According to the above definition, which of the following situations may lead to secondary succession:
When the forest was cut down repeatedly, it evolved into a sparse grassland