Researchers have found that the bacteria, Helicobacter pylori accounts for 80% of all stomach ulcers occurring in the population. What type of measure is that

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.

frogs. the lower the ph the higher the acid content. frogs have the highest tolerance in this scenario.

the answer would be..

b. sucking