What is consumer lag, how is it calculated, and why is it important for service level agreements?

What is consumer lag, how is it calculated, and why is it important for service level agreements?

• A. Lag is the number of unprocessed messages in the broker memory.
• B. Lag is the difference between the consumer's last consumed offset and the earliest offset.
• C. Lag is the amount of time since the last poll.
• D. Lag = difference between the latest log end offset and the consumer's last committed offset. It indicates how far behind a consumer is and helps monitor throughput and latency.

Answer: (D)