Refer to the exhibit. An engineer receives an error when applying low latency queuing on a new switch. What is causing this policy to fail?

While a 'priority' queue can optionally have a 'bandwidth' limit, its absence does not typically cause the entire LLQ policy to fail upon application; it simply means the priority queue has no explicit rate limit.

A 'set' statement within a policy map does not necessarily require an immediate subsequent action; its purpose is usually to mark traffic, which can be an endpoint action for a class.

While traffic marking can be performed in a separate policy or on an ingress interface, this is a design choice and not a reason for an LLQ policy to fail upon application.

Low latency queuing (LLQ) is primarily an egress QoS feature, meaning it must be applied on the outbound direction of an interface ('service-policy output') to correctly prioritize and queue traffic as it leaves the device. Applying it inbound ('service-policy input') will result in an error or incorrect behavior because queuing decisions are made on transmission.