Question

{"given":"The question asks about molluscan groups and their eye structures, specifically which group has eyes that resemble vertebrate eyes. The four major molluscan classes are being compared for their eye complexity and similarity to vertebrate visual systems.","key_observation":"Cephalopods (class Cephalopoda) are the only molluscan group that has evolved camera-type eyes with remarkable similarity to vertebrate eyes. These eyes have a lens, cornea, iris, and retina arranged in a structure functionally equivalent to vertebrate eyes, representing a classic example of convergent evolution where similar environmental pressures led to similar anatomical solutions.","option_analysis":[{"label":"(A)","text":"Bivalvia","verdict":"incorrect","explanation":"Bivalves like clams and mussels have very simple photoreceptive organs or eyespots along their shell margins, but these are not complex eyes and certainly do not resemble vertebrate eyes in structure or function."},{"label":"(B)","text":"Gastropoda","verdict":"incorrect","explanation":"Gastropods like snails have simple eyes that can detect light and movement, but they lack the complex lens system and retinal organization found in vertebrate eyes."},{"label":"(C)","text":"Pelecypoda","verdict":"incorrect","explanation":"Pelecypoda is an outdated taxonomic name that refers to the same group as Bivalvia. These organisms have only simple light-detecting structures, not complex eyes resembling vertebrates."},{"label":"(D)","text":"Cephalopoda","verdict":"correct","explanation":"Cephalopods including squids, octopus, and cuttlefish have sophisticated camera-type eyes with a lens, cornea, iris, and retina that are structurally and functionally very similar to vertebrate eyes, making this the correct answer."}],"answer":"(D)","formula_steps":[]}