"Transaction Monitoring Systems and Ongoing Monitoring: Since the transactional monitoring system is key to mitigating ML risk within the bank, the Committee recognizes that AML risks require more than just appropriate policies and procedures; banks must have adequate and appropriate monitoring systems. For most banks, this will involve an IT monitoring system. If the bank does not believe it needs an IT monitoring system, it should document the rationale for why it does not need one.

This involves breaking down large amounts of cash into smaller transactions that are below the reporting threshold of $10,000 in the United States, in order to avoid detection and reporting by the financial institution.
Structuring is a red flag for money laundering and should be reported to the authorities as a suspicious activity.
The other options are not necessarily indicative of money laundering, as they could have legitimate explanations. For example, the customers may have a family or business connection to the same recipient in Country B, or they may have a regular need to send money three times a week.
References:
* ACAMS CAMS Certification Video Training Course, Chapter 2: Money Laundering Risks and Methods, Section 2.2: Common Money Laundering Techniques
* Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition), Question 91
* CAMS Certification Package - 6th Edition, Study Guide, Chapter 2: Money Laundering Risks and Methods, Page 38

Economic sanctions are a tool that governments and multi-national bodies can use to prevent the proliferation of weapons of mass destruction (WMDs) by imposing restrictions on trade, financial transactions, travel, or other activities with targeted countries, entities, or individuals that are involved or suspected of being involved in WMD programs. Economic sanctions aim to disrupt the supply chains, funding sources, and incentives for developing or acquiring WMDs, as well as to deter and punish any violations of international norms and obligations regarding WMDs. Economic sanctions can be imposed unilaterally by a country or multilaterally by a group of countries or an international organization, such as the United Nations, the European Union, or the Financial Action Task Force.
References:
ACAMS CAMS Certification Video Training Course, Module 4: Preventing the Proliferation of Weapons of Mass Destruction, Lesson 4.2: Sanctions1 ACAMS CAMS Certification Study Guide, 6th Edition, Chapter 4: Preventing the Proliferation of Weapons of Mass Destruction, Section 4.2: Sanctions2

Explanation/Reference: https://www.fatf-gafi.org/media/fatf/documents/brochuresannualreports/FATF30-(1989-2019).pdf