Explanation
The primary reason to perform a risk assessment is to determine the current risk profile of the organization, which is the level of risk exposure and the likelihood and impact of potential threats. This will help the organization to identify and prioritize the risks that need to be addressed and to align the risk management strategy with the business objectives. A risk assessment may also help to achieve compliance, support the BIA, and allocate budget, but these are not the primary reasons. References: ISACA Glossary of Terms, section
"risk assessment"

The best recommendation to mitigate the risk of eavesdropping associated with an API integration implementation is to implement Transport Layer Security (TLS). TLS is a cryptographic protocol that provides secure communication over a network by encrypting the data in transit and authenticating the parties involved.
TLS can prevent unauthorized parties from intercepting, modifying or tampering with the data exchanged between the API endpoints. Encrypting the XML file, implementing SOAP, and masking the API endpoints are not sufficient to mitigate the risk of eavesdropping, as they do not provide end-to-end encryption or authentication for the API communication. References: IS Audit and Assurance Tools and Techniques, CISA Certification | Certified Information Systems Auditor | ISACA

The best way to mitigate the risk associated with unintentional modifications of complex calculations in end-user computing (EUC) is to execute copies of EUC programs out of a secure library. This will ensure that the original EUC programs are protected from unauthorized changes and that the copies are run in a controlled environment. A secure library is a repository of EUC programs that have been tested, validated, and approved by the appropriate authority. Executing copies of EUC programs out of a secure library can also help with version control, backup, and recovery of EUC programs. Having an independent party review the source calculations, implementing complex password controls, and verifying EUC results through manual calculations are not as effective as executing copies of EUC programs out of a secure library, as they do not prevent or detect unintentional modifications of complex calculations in EUC. References: End-User Computing (EUC) Risks: A Comprehensive Guide, End User Computing (EUC) Risk Management