The rules imposed by the Office of Foreign Assets Control (OFAC) for legal entities and persons related to the US are:
Nationals of the US must comply with OFAC rules, regardless of where they are located in the world. This means that US citizens, permanent residents, and entities organized under US law are subject to OFAC sanctions and prohibitions, even if they operate or reside outside the US12.
Any foreign corporation is also penalized if it conducts transactions with sanctioned countries under OFAC rules. This means that non-US entities that engage in trade or financial dealings with OFAC-designated countries, entities, or individuals are liable to face civil or criminal penalties, as well as secondary sanctions that could restrict their access to the US market or financial system34.
The other options are not correct, because:
A subsidiary of a legal entity of the US, which is formally registered in a foreign country, is not exempt from OFAC rules. This means that foreign-incorporated entities that are owned or controlled by US persons or entities are also subject to OFAC sanctions and prohibitions, unless they are specifically authorized or licensed by OFAC12.
A foreign individual visiting the US for a short vacation is not obligated to follow OFAC rules. This means that non-US persons who are temporarily present in the US are not subject to OFAC sanctions and prohibitions, unless they are involved in transactions that have a US nexus or violate other US laws.
The head office of a foreign legal entity which has a branch in the US does not need to comply with OFAC rules. This means that non-US entities that have a presence or operation in the USare not subject to OFAC sanctions and prohibitions, unless they are involved in transactions that have a US nexus or violate other US laws.
[References:, ACAMS CAMS Certification Video Training Course - Exam-Labs3, Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition)4, ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 147: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf, ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 148: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf, ACAMS Study Guide for the Certification Examination, 6th Edition, Chapter 7, page 149: https://www.acams.org/wp-content/uploads/2019/08/ACAMS-Study-Guide-6th-Edition-Chapter-7.pdf, , ]