What did harry harlow demonstrate in his classic study of attachment amongst baby monkeys?

The monkeys were more attached to the artificial mothers that were warm and soft.

Explanation:

Since monkeys are considered to one of the closest primate to humans, harry Harlow intended to gather information regarding parent-child relations among humans by studying how other primates would behave under similar situation.

The monkeys were more attached to the artificial mothers that were warm and soft indicates that emotional bonding between children and parents in primates starts from early age. Warm and Soft atmosphere provided a sense of comfort for the children that later turned into long time affection to their parents.

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.