The correct answer is that it indicates a potential unauthorized access attempt which the firewall has blocked. This is consistent with entries in server logs for denied connections, which often suggest that a firewall or similar security appliance is actively preventing access from unrecognized or untrusted sources, and is particularly notable when this activity occurs during non-business hours, suggesting a possible attack. A Distributed Denial of Service (DDoS) attack would likely not just appear as denied connections but would also come with a significant increase in traffic, potentially overwhelming the network's capacity. Performance issues or misconfiguration are less likely to generate multiple denied connection log entries from various external IP addresses.