On a long transcontinental flight, a middle-aged man gets up and exercises in the aisle, moving his hands, feet, arms, and legs as much as he can. he does this every two hours. the flight attendant asks him to sit down, but he explains that he is trying to prevent a very dangerous medical condition. he is talking about

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.