What was one reaction the United States had to Cuba taking over property owned by Americans? The U. S. threatened a nuclear attack
The U. S. put an embargo on Cuban goods
The U. S. wanted Cuba to trade with other countries
An agreement was reached to limit the number of Cubans entering the U. S

Idont know which one is right   but i know that c is wrong and a might be wrong

Ifound the exercise on the internet. attached is the list mentioned above.in order for a compound to be considered optically active it can't have any axis or plan of symmetry. the molecule  shouldn't also  be superimposable on its mirror image.with such considerations, the compounds that are optically active are: -third compound on the first image is optically active; -second and third compound from the second image are optically actives.