Answer:
A) Cultural differences
Step-by-step explanation:
The Foreign Corrupt Practices Act prohibits US citizens (including companies) from bribing foreign individuals in order to obtain commercial benefits.
It might be hard to believe, but this type of law is very uncommon, for example European nations don't have similar laws, I guess South American countries don't have them either. And our western culture basically includes parts of Europe, North and South America, and Australia. So even those who share similar cultural values do not have this law.
Cultural differences refers to different beliefs, cultural practices, religion, behaviors, etc. As stated above, the US culture is included under the western culture category, since the general cultures and beliefs of these countries are similar (or at least not as different as Asian or African countries).