Which statement describes a learned behavior? O A. A dog lifts its paw to shake hands when its owner snaps her
fingers.
B. A turtle pulls into its shell when it first encounters a human.
O C. A robin builds a nest using mud, grass, and small twigs.
O D. A baby deer drinks its mother's milk when it's hungry.

coral.

explanation:

coral. many marine organisms that produce calcium carbonate shells or skeletons are negatively impacted by increasing co2 levels and decreasing ph in seawater.

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.