This is a typical question with many concepts to confuse. The key is to look at the incident; the incident involved an employee using a TABLET, downloading a file, and then uploading it to a competitor's cloud. The text does not specify that the employee used their own cloud to transfer the file, which would be odd, meaning they would download the file and then place it on their own cloud, and then what, grant access to the competitor? It doesn't make sense. In my opinion, the best solution is an MDM with specific policies prohibiting the download and exfiltration of data. The key point is that they mention it was a tablet. The answer, in my view, is MDM.

mdm is the answer

Not MDM because you need MAM to stop prevent this.

The CASB serves as a policy enforcement center, consolidating multiple security policy enforcement functions and applying themto everything your business uses in the cloud—regardless of the kind of device attempting to access it, including unmanaged smartphones and personal laptops. The company took special precautions by using proper labels for data. If you set such a CASB policy that restricts uploading those data that was labeled as sensitive, one cannot upload it to the cloud storage. measures such as containerization or encryption. References: https://www.blackberry.com/us/en/solutions/corporate-owned-personally-enabled https://www.professormesser.com/security-plus/sy0-601/sy0-601-video/mobile-device-management/

were downloaded from the cloud and passed to the cloud. B

MDM is not correct, because you can't prevent an employee to download company's data to his device, when he is really in need of that data. so MDM won't work. the only behavior that pass the line is, he uploaded the data to the cloud. this is should be blocked. I see some argue CASB is only for own cloud, well, CASB can be installed in 3rd party cloud, search for "CASB AWS" and you will see how amazon provide CASB to his customer.

mobile device management

Here's why: MDM solutions provide centralized control over mobile devices, allowing organizations to enforce security policies, manage device configurations, and remotely monitor and manage devices. By implementing MDM, the company can: Enforce security policies: MDM allows the company to enforce policies such as data encryption, device passcode requirements, and restrictions on data sharing to prevent unauthorized access to sensitive information. Monitor and manage devices: MDM solutions enable the company to remotely monitor device activity, track device location, and remotely wipe devices in case of loss or theft. This helps prevent unauthorized access to sensitive data stored on the device. Control app installation and usage: MDM allows the company to control which apps can be installed and used on employee devices. This can prevent employees from using unauthorized apps or accessing unauthorized cloud storage services where sensitive data could be leaked.

After putting some thought into this question, here is what I think the important factor is. The question states "documents were downloaded from an employee's COPE tablet". This seems to me to be the point of failure in the scenario. Having said that, I think the best option to correct that would be MDM. With MDM the data would be protected through classification and tagging (which is stated in the scenario) and the use of data encryption.

not casb on this one guys

B. CASB In this scenario, a CASB could have prevented the employee from downloading sensitive documents from the corporate network to their personal device, or from uploading them to a cloud storage service that is not sanctioned by the company.

Along with DChilds comments regarding other similar questions, I'd like to add question 698 as a reference for you all. You'll see again that MDM is not an option. and CASB is the correct answer.

CASB is only going to work if the data was uploaded via the company's cloud storage, if they were using the competitor's cloud storage (which they did), CASB would be useless. B) is definitely the wrong answer.

With MDM you can block app store which can prevent this

If the COPE device doesn't have an MDM solution, the employee can disconnect from the company network and connect to a hotspot to a public network, where there is no DLP or CASB ,bypassing all company network security.

B. CASB The data was labeled. That means a DLP policy would detect the exfiltration. A CASB often has a DLP functionality. So a CASB with DLP functionality would have detected the data exfiltration.

B. CASB: This stands for cloud access security broker, a tool that can monitor and control the access and usage of cloud services by COPE devices. This can help prevent unauthorized data transfers and enforce data loss prevention policies.