A company uses cloud-based applications for voice and video calls, file sharing, content sharing, and messaging. During business hours, these applications randomly become slow and unresponsive. However, other applications work smoothly with the current applied QoS policies. Which solution must the company choose to resolve the issue?
A. dentify the port used by each application and apply a minimum bandwidth guarantee
B. dentify the application ports, create groupings, and rate-limit the required bandwidth
C. dentify the applications and reserve the required bandwidth on the perimeter routers
D. dentify the applications with NBAR2 and allocate the required bandwidth accordingly