Soft-bodied animals that features some speices that have an external shell are called b. planarians c. annelids d. mollusks

Planarians - These are aquatic flattened-out worms (flat worms) that have a rather "primitive" aspect but also feature some very important evolutionary aspects. They do not feature shells/

Annelids - These are worm-like organisms, that live under humid conditions, and do not feature shells.

Mollusks - These also have soft bodies, like the first two, and they're also invertebrates. They feature external calcium-based shells.

Hope it helped,

BioTeacher101

increase soil erosion                                             reduce soil erosion

cattle grazing                                                         hydroseeding

deforestation                                                         contour plowing

                                                                                planting vegetation

plant roots basically hold the top soil

together and stop soil erosion because

in such situation top soil is not removed

during flood but cattle grazing causes

soil erosion because cattle consume the

grasses and herbs and top soil is exposed.

same situation occurs because of

deforestation, the trees and plants are cut

down to expose top soil which causes soil

erosion