Both chordates and invertebrates have pharyngeal pouches
Answer:
the answer is c.
oceanic acidification is occurring, which results in shelled creatures, clams, lobster, to have weaker shells as a defense. the shells break easily and are too weak to protect the organisms inside, unable to properly calcify their shells leaves them vulnerable to preditors...
Well theory isnt proven. It means you have a strong idea about the subject your talking about. So if a scientist finds evidence that suggests something against the theory then it can be changed.