The training of animals usually involves
imprinting
classical conditioning
operant conditioning
cognitive learning

operant conditioning

Explanation:

Operant conditioning, also called instrumental conditioning, is a learning method that makes use of the association of reinforcements (rewards) and punishments with a particular behavior or pattern of behavior. Through operant conditioning, an association is made between a behavior and a consequence of that behavior. This method is widely used in animal training.

Operant conditioning is based on a simple premise: actions followed by reinforcement will tend to repeat themselves. On the other hand, actions that result in unintended punishments or consequences will weaken and are less likely to occur again in the future.

An example: When a lab rat presses a blue button, he receives a food ball as a reward, but when he presses the red button, he receives a slight electric shock. As a result, he learns to press the blue button but avoids the red button.

they deliver oxygen to the blood

the index of refraction of the second medium is higher. i just took the test trust me !