Question - Descent into madness

Hungering souls node - “souls deal more damage over time”
To which does this apply:
A) Souls innately have necrotic DoT on hit.
B) Caustic wretches/decayed mind and fire skull/eternal pyre (HS nodes) apply ailments on hit
C) On-hit effects/ailments like bleed and ignite from other sources (items/idols, etc).

It reads like all DoT since it does not specify, but can anyone confirm?

It should be any DoT that the skill inflicts.