The correct option is
C Panacea
Option B - 'Cure' means something that makes someone who is sick healthy again. Thus option B is incorrect.
Option C - 'Antibiotic' is a medicine or a chemical that can destroy harmful bacteria in the body or limit their growth. Thus option C is incorrect.
Option D - 'Remedy' is a successful way of curing an illness or dealing with a problem or difficulty. Thus option D is incorrect.
Option A - 'Panacea' is something that will cure all diseases. Thus option A is the correct answer.
'A cure for all diseases - Panacea'