Three-month-old Lionel loved to suck on his fingers. He was quite fond of putting his fingers in his mouth and then pulling them out only to look them over for a minute or two before putting them back in his mouth. He repeated this behavior over and over. Lionel's behavior with his fingers illustrates a:

primary circular reaction.

Explanation:

Primary Circular Reaction is the second substage of the Sensorimotor Stage of Cognitive Development.  

The Sensorimotor stage is the early stage in the Cognitive Development theory of Jean Piaget. In this stage of cognitive development, an infant learns to grow and develop through various trials.  

In Primary Circular Reaction stage of cognitive development, an infant learns to grow and develop through various trials. In this stage, an infant develops new schemas. A baby starts repeating the actions that they find pleasurable.  This stage occurs between the age of 1-4 months..

In the given case, Lionel's repeating behaviour of sucking his fingers is an example of Primary Circular Reaction. Lionel has developed a new schema of sucking his fingers which he finds pleasurable that he puts his fingers after every minute or two.  

So, the correct answer is Primary Circular Reaction.

the correct answer is modern american cars are not available due to trade restrictions.

trade between cuba and the united states have serious restrictions. the u.s. imposed an economic embargo on cuba, that among other things means that modern american cars are not available due to trade restrictions.

in response to some governmental actions of the authorities from cuba, president john f. kennedy proclaimed an embargo on trade between both countries in february 1962. the trade embargo remains active until this day and was implemented directly by the departments of commerce and the department of treasury.

in president trump’s administration, there is a national security presidential memorandum that "strengthens the policy of the u. s.", affecting trade with cuba.