The mineral particles found in the layers of a soil, including the topsoil and subsoil layers, were originally weathered from
A.
the soil's humus.
B.
organisms living in the soil.
C.
the soil's parent material.
D.
the soil's groundwater.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

answer; benefit; harmed;

barometer is an instrument used to measure the atmosphere's pressure. the high air pressure relative to average levels is associated with calm and sunny weather. on the other hand, low pressure is associated with bad weather, high winds, and rain.