I Often Find That When I Am Ill, I Am

I often find that when I am ill, I am not able to cope effectively with the normal hassles of life. I find myself becoming irritated by things that I would usually be able to ignore. Which of the following would explain this phenomenon?

A) When using resources to deal with one stressor, the ability to tolerate additional stressors may be compromised.
B) Major life changes may impair the ability to cope effectively with daily hassles.
C) During the exhaustion phase of the general adaptation syndrome illness becomes likely.
D) Allostatic load leads to psychological and biological vulnerability.