The correct answer among all the other choices is C. Advancements in travel and communication allowed this change. This is the statement that does not describe the 20th Amendment. Thank you for posting you question. I hope this answer helped you. Let me know if you need more help.
It affected them immeasurably because it enabled them to trade this surplus of food for things that they might need from other countries and thus get other pieces of technology or knowledge or anything similar. They could improve their state that way and that's how development of civilizations began.
It would be that "d. Muhammad was engaged in long-distance trade where he came into contact with monotheists" that likely would have influenced his acceptance of monotheism, since this allowed for him to gain new and challenging points of view.