Which tool is needed to monitor server applications in the company's data center?

The appropriate tool for monitoring server applications within a data center is SNMP (Simple Network Management Protocol). SNMP is specifically designed to facilitate the monitoring and management of network devices and applications, allowing administrators to collect performance data, monitor application health, and receive alerts on system status. By using SNMP, IT teams can gain insights into resource usage, system errors, and other metrics that are critical for maintaining optimal performance.

The other options, while related to different aspects of network and system management, do not directly serve the purpose of monitoring server applications. For instance, SMS (Short Message Service) is primarily for sending text messages, and is not used for server monitoring. SMTP (Simple Mail Transfer Protocol) is utilized for sending emails, which could be part of alerting mechanisms but again, not for actual monitoring. IPMI (Intelligent Platform Management Interface) is more focused on hardware management and provides out-of-band management capabilities, which can include monitoring but is specifically oriented toward physical hardware rather than application-level performance.