The black soil that the Nile left on the flooded Egyptian land was called . A.
silt
B.
mud
C.
moss
D.
fertilizer

A. Silt

Explanation:

Silt is generally considered the soft, nutrient rich soil carried downstream by a river. Mud is just any significantly wet dirt. Moss is a type of biological growth. Fertilizer is generally considered to be anything man-made which gives plants additional nutrients.

chemical weathering

explanation:

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.