Introduction:
Performance management is a process that involves monitoring and measuring the performance of a system, network, or application to ensure that it is meeting the desired objectives. It allows organizations to identify and address any performance issues or bottlenecks to optimize the overall performance. Fault management, on the other hand, is the process of detecting, diagnosing, and resolving faults or errors in a system. While performance management and fault management are related, they serve different purposes in managing and maintaining the performance of a system.

Explanation:
1. Proactive Fault Management:
Proactive fault management involves taking preventive measures to identify and resolve potential faults or issues before they impact the performance of a system. It focuses on identifying and addressing the root causes of faults, rather than just fixing the symptoms. However, proactive fault management is not directly related to performance management. It aims to minimize the occurrence of faults, but it does not focus on measuring and optimizing the performance of a system.

2. Reactive Fault Management:
Reactive fault management is the process of detecting and resolving faults or errors in a system after they have occurred. It involves monitoring and alerting systems that notify administrators or operators about the occurrence of faults. Reactive fault management focuses on restoring the system to its normal state and minimizing the impact of faults on the overall performance. While reactive fault management is important in maintaining the performance of a system, it is not synonymous with performance management.

3. Fault Management:
Fault management, as mentioned in the correct option, is closely related to performance management. It involves the identification, diagnosis, and resolution of faults or errors in a system. When a fault occurs, fault management systems detect and isolate the fault, collect relevant information, and take appropriate actions to resolve the issue. Fault management is an integral part of performance management as it helps in maintaining the desired performance levels by addressing any faults or errors that may impact the system's performance.

Conclusion:
While proactive fault management and reactive fault management are important in maintaining the performance of a system, fault management, in general, is closely related to performance management. Fault management helps in identifying and resolving faults or errors that may impact the performance of a system, thereby ensuring optimal performance. Therefore, the correct answer to the given question is option 'B' - Fault management.