Which describes a difference between cephalopods and gastropods? A) Cephalopods have a water vascular system, and gastropods have an open circulatory system.
B) Cephalopods live only in ocean environments, and gastropods live in a variety of environments.
C) Cephalopods have a simple nervous system, and gastropods have a complex nervous system.
D) Cephalopods are the largest group of mollusks, and gastropods are the smallest group of mollusks.

On the bahamian island of andros, mosquitofish populations live in isolated freshwater ponds that were once united. currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; predator-poor ponds have mosquitofish that can swim continuously for a long time. when placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences. if one builds a canal linking a predator-rich pond to a predator-poor pond, then what type(s) of selection should subsequently be most expected among the mosquitofish in the original predator-rich pond, and what type(s) should be most expected among the mosquitofish in the original predator-poor pond?