9. The fall of the ranching, wheat-growing, and oil industries caused

true is the answer to this

d: social contract theory

b: to eliminate competition from other farmers

so, based on the research i've done. the u.s. government were always on a wild goose chase just to take down castro. he then retired his trone to his brother raul in 2008 due to some health issues. so it's obvious your answer would be:

castro had no allies from which he could receive aid.

hope this and have a fantastic day!

                                                    -wolfiewolffromsketch