Reactive Problem Management

Answer:
Reactive Problem Management is triggered (usually) by Incident management process. Incident Management has task to resolve incident as soon as possible and provide the user with the service. Reactive Problem Management has task to find root cause of one or more incidents. For example: user calls Service Desk while he has his PC stuck and sees only blue screen. Incident Management implements workaround to resolve incident i.e. advises a user to restart a PC. But, it's still not known what has caused this incident. That's the job of Problem Management. They start investigation, diagnosis, analyse...
Read this article to learn more: ITIL Reactive and Proactive Problem Management: Two sides of the same coin https://advisera.com/20000academy/knowledgebase/itil-reactive-proactive-problem-management-two-sides-coin/