Out of the four alternatives choose the one which can be substituted for the given words/sentences.
One who cannot be corrected:
Option B is the right answer.
An incorrigible person/behavior is something that can’t be corrected. Source: https://dictionary.cambridge.org/dictionary/english/incorrigible
Option A incurable(adj): something that can’t be cured
Option C hardened(adj): to make hard
Option D invulnerable(adj): impossible to harm or damage