A cure for all diseases

Answer: Option C

One word substitute is Panacea.

Exorcism: the religious or spiritual practice of evicting demons or other spiritual entities from a person, or an area, that are believed to be possessed.
Incantation: a series of words said as a magic spell or charm.
Panacea: a solution or remedy for all difficulties or diseases.
Antibiotic: a medicine (such as penicillin or its derivatives) that inhibits the growth of or destroys microorganisms.