I don't quite understand why you would include that last part, since if there is death, or if there is endangerment of people's lives, or if there is a risk to health or safety, those are freestanding offences. I don't see why you're qualifying “causes serious interference” with (A) through (C).
En effet, s'il s'agit d'une activité terroriste, les divisions (A) et (B) suffisent, puisqu'il y est déjà question d'intention et que l'on aura déjà causé des perturbations graves, et je n'entends pas une grève ou une manifestation.