Which transformation requires a complete meltdown of the rock into magma? a. igneous rock to sedimentary rock b. sedimentary rock to metamorphic rock c. metamorphic rock to sedimentary rock d. sedimentary rock to igneous rock e. igneous rock to metamorphic rock

Igneous rocks are formed by the cooling of the magma.

Sedimentary rocks are formed by weathering and erosion of igneous rocks and then consolidation of the sediments.

Metamorphic rocks are formed when igneous or sedimentary rocks are subjected to heat and pressure.

The metamorphic rocks melts and forms magma which in turn cools down to form igneous rocks.

Similarly, sedimentary rocks melt down and forms magma which cools down to form igneous rocks.

So, the igneous rock is formed by cooling of magma, which is in turn formed from sedimentary and metamorphic rocks.

Of the given options only one option has the resulting rock as igneous.  

Hence the answer is

sedimentary rock to igneous rock

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

the glands which are associated with each description is given below: