NetFlow is a network protocol developed by Cisco for the collection and monitoring of network traffic flow data generated by NetFlow-enabled routers and switches. The flows do not contain actual packet data, but rather the metadata for communications. It is a standard form of session data that details who, what, when, and where of network traffic -> Answer A is not correct.
Reference:
white-paper-c11-736595.html

In this IaaS model, cloud providers offer resources to users/machines that include computers as virtual machines, raw (block) storage, firewalls, load balancers, and network devices.
Note: Cloud access security broker (CASB) provides visibility and compliance checks, protects data against misuse and exfiltration, and provides threat protections against malware such as ransomware.

When supporting personal devices on a corporate network, you must protect network services and enterprise data by authenticating and authorizing users (employees, contractors, and guests) and their devices. Cisco ISE provides the tools you need to allow employees to securely use personal devices on a corporate network.
Guests can add their personal devices to the network by running the native supplicant provisioning (Network Setup Assistant), or by adding their devices to the My Devices portal.
Because native supplicant profiles are not available for all devices, users can use the My Devices portal to add these devices manually; or you can configure Bring Your Own Device (BYOD) rules to register these devices.
Reference:
m_ise_devices_byod.html