Science
Set A: The clam in set Starts with Aa its a large smooth discolored clam. Then I have Ba which are small white oval shell theyre also smooth. Then I have Ca which is large smooth spiral clam. Next, is Da which is a more plumped looking shell that is connected to Ec a spiraled medium sized clam, also looks rough. Da is also connected to Ea a small smooth round clam. Da is lastly connected to Fa which are spike spiral clams. The shell start with a small smooth surface than moves to more spiraled shell like in Ja which lead to spiked thick line shells (Ga) that are small
Set B the differences between this group is shells and clams. The shells starts off with a small spike shell, next the shells are smooth curved a little and thin. After, that one shells have line imprinted on them and it looks like they have multiple layers along with some cracks in them. On the other side there are clams which starts off with a round smooth clam then you have other clams which are oval shaped some smooth, with spirals, weird shape, or spikes.
Set C: on the shell side it start with a small shell, next you have medium size shells they also look like they have multiple layers and lines that are either vertical or horizontal. Some shells are chipped. Then theres (Ia) the next set of shells some are dark. These shells are shiny and flat like with a circular shape. Lastly, Ja shells come after Ia which has all components of the other shells which they have multiple layers along with lines or strips. A few have holes in them. The clams transition starts with Aa a small shell which moves on to Ba shells those are small and oval shaped and shiny. Next, is Ca those look like hermit crab shells some are smooth and others have lines. Those are connected to Da which are spiked shells