Social engineering is a technique used by attackers to manipulate individuals into divulging sensitive information or performing actions that can compromise the security of an organization. Multi-factor authentication (MFA) is a security mechanism that requires users to provide at least two forms of authentication to verify their identity. By requiring MFA, even if an attacker successfully obtains a user's credentials through social engineering, they will not be able to access the network without the additional form of authentication.

Wiping the device remotely is the best option to minimize the risk of data exposure from a stolen personal mobile device. This action will erase all the data stored on the device, including the sensitive corporate data, and prevent unauthorized access or misuse. Wiping the device remotely can be done using enterprise mobility management (EMM) or mobile device management (MDM) tools that allow administrators to remotely manage and secure mobile devices. Alternatively, some mobile devices have built-in features that allow users to wipe their own devices remotely using another device or a web portal.
Preventing the user from using personal mobile devices is not a feasible option, as it may affect the user's productivity and convenience. Moreover, this option does not address the immediate risk of data exposure from the stolen device.
Reporting the incident to the police is a good practice, but it does not guarantee that the device will be recovered or that the data will be protected. The police may not have the resources or the authority to track down the device or access it.
Removing the user's access to corporate data is a preventive measure that can limit the damage caused by a stolen device, but it does not eliminate the risk of data exposure from the data already stored on the device.
The user may have cached or downloaded data that can still be accessed by an attacker even if the user's access is revoked. References = Guidelines for Managing the Security of Mobile Devices in the Enterprise NIST Special Publication, Section
3.1.11, page 3-8
CISM Review Manual, Chapter 3, page 121
Mobile device security - CISM Certification Domain 2: Information Risk Management Video Boot Camp
2019, Section 3.3, 00:03:10

Ensuring encryption for data in transit is the best activity that supports the concept of confidentiality within the CIA triad, as it protects the data from unauthorized access or interception while it is being transmitted over a network. Encryption is a technique that transforms data into an unreadable form using a secret key, so that only authorized parties who have the key can decrypt and access the data. Encryption standards include AES (Advanced Encryption Standard) and DES (Data Encryption Standard).
References = CISM Review Manual 2022, page 321; CISM Exam Content Outline, Domain 1, Knowledge Statement 1.12; The CIA triad: Definition, components and examples3; CIA Triad - GeeksforGeeks4

= Testing response scenarios is the most important factor in increasing the effectiveness of incident responders, as it allows them to practice their skills, identify gaps and weaknesses, evaluate the adequacy and feasibility of the incident response plan, and improve their coordination and communication. Testing response scenarios can also help to enhance the confidence and readiness of the incident responders, as well as to measure their performance and compliance with the policies and procedures. Testing response scenarios can be done through various methods, such as tabletop exercises, simulations, drills, or full-scale exercises, depending on the scope, objectives, and complexity of the scenarios.
The other options are not as important as testing response scenarios, although they may also contribute to the effectiveness of incident responders. Communicating with the management team is important to ensure that the incident responders have the necessary support, resources, and authority to carry out their tasks, as well as to report the status and outcomes of the incident response. However, communication alone is not sufficient to increase the effectiveness of incident responders, as they also need to have the relevant knowledge, skills, and experience to handle the incidents. Integrating staff with the IT department may help to facilitate the collaboration and information sharing between the incident responders and the IT staff, who may have the technical expertise and access to the systems and data involved in the incidents. However, integration alone is not enough to increase the effectiveness of incident responders, as they also need to have the appropriate roles, responsibilities, and processes to manage the incidents. Reviewing the incident response plan annually is important to ensure that the plan is updated and aligned with the current risks, threats, and business requirements, as well as to incorporate the lessons learned and best practices from previous incidents.
However, reviewing the plan alone is not enough to increase the effectiveness of incident responders, as they also need to test and validate the plan in realistic scenarios and conditions. References = CISM Review Manual, 16th Edition, ISACA, 2022, pp. 223-225, 230-231.
CISM Questions, Answers & Explanations Database, ISACA, 2022, QID 1004.