During the sequencing of the chimpanzee genomes, a gene (cmah) was identified that completely lost an exon in human when compared to chimpanzee. scientists have found no evidence of the protein or its enzyme function in any human tissue although the protein is fully functional in chimpanzee. the normal function of the gene is to add modified sialic residues to proteins on the cell membrane. the loss of the exon is found in all humans that have been examined, but the gene is conserved in all other primates and mammals

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.

the answer will be a) proteins i believe