I am not a teacher.
This sounds like a management training manual.
a) 'To assume a life of its own', 'to take on a life of its own', or other similar forms usually mean that the thing being spoken about has gone beyond the control of whoever created it.
b) Yes, 'they' does refer to the crises.
c) 'These difficult questions' refers to examining 'the things that are of the greatest risk...' mentioned in the third sentence. The leader is supposed to motivate the employees (when all is going well) so that they will ask these questions.
Student or Learner