The characteristic of the Financial Action Task Force (FATF) 40 recommendations is that they comprise global standards for countering money laundering, recognized by government bodies across the world. The FATF 40 recommendations provide a comprehensive framework of measures that countries should implement to combat money laundering and terrorist financing. The recommendations are not mandatory, but are widely recognized and followed by countries across the globe. The recommendations cover a range of areas, including customer due diligence, record-keeping, suspicious activity reporting, and international cooperation.

Physical certificates are documents that represent ownership of securities, such as stocks or bonds, that are issued by a company or a government. Physical certificates present a money laundering risk to broker-dealers for two reasons:
The trade information on a physical certificate can be easily altered, such as the name of the owner, the date of issuance, or the number of shares. This can facilitate the concealment or falsification of the origin, ownership, or value of the securities, and enable the laundering of illicit funds through the purchase or sale of the securities.
Physical certificates may be provided to nominees for deposit or settled in off-market transactions, such as private placements, bearer bonds, or direct transfers. This can bypass the normal reporting or recordkeeping requirements of the broker-dealer, and avoid the scrutiny or verification of the identity, source of funds, or beneficial ownership of the securities.
Two Reasons Physical Certificates Pose Money Laundering Risks to Broker ...
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According to the ACAMS CAMS Certification Study Guide (6th edition), the bank should file a SAR if it knows, suspects, or has reason to suspect that a transaction involves funds derived from illegal activity, or is intended or conducted to hide or disguise funds or assets derived from illegal activity, or to evade any BSA regulation or federal law, or has no business or apparent lawful purpose, or is not the sort in which the customer would normally be expected to engage1. The scenario described in the question meets these criteria, as the small deposits and withdrawals from a high-risk country could indicate money laundering, terrorist financing, or other illicit activities. The bank should also document its decision to file or not file a SAR, and retain thesupporting documentation for five years1.
The other options are not correct because they either do not comply with the BSA requirements, or do not adequately address the potential risk of the activity. Blocking any further activity could alert the customer of the bank's suspicion, and could also interfere with law enforcement investigations. Initiating an investigation into the activity could be part of the bank's due diligence process, but it does not substitute the obligation to file a SAR if the activity is suspicious. Contacting the customer could also tip off the customer, or elicit false or misleading explanations that could hinder the bank's assessment of the activity.
ACAMS CAMS Certification Study Guide (6th edition), page 82-83. 12345678 [9]

Civil and Criminal Prosecution, Fines, and Imprisonment: The Chief AML Officer may face legal action, including both civil and criminal proceedings. This could result in fines and even imprisonment if found guilty of negligence or misconduct related to anti-money laundering compliance.
Ban from Employment: Regulators have the authority to ban individuals from working in the financial services industry if they are deemed unfit due to AML-related failures. Such a ban can significantly impact the individual's career prospects.
Recommend Termination of Employment: While the regulator cannot directly terminate employment, they can recommend that the financial institution (FI) take appropriate action, including termination, based on the Chief AML Officer's performance.
References:
Anti-Money Laundering Specialist (the 6th edition) resources.
ACAMS AML Glossary (definitions of terms related to AML).1
ACAMS AML Foundations Certificate (overview of AML concepts and responsibilities).2 ComplyAdvantage: 6th Money Laundering Directive (6AMLD) (details on AML regulations and penalties).3