A pioneer of a reform movement

A. Renegade

B. Apostle

C. Apotheosis

D. Apothecary

Answer: Option B

Solution(By Examveda Team)

One word substitute is Apostle.

Renegade: a person who deserts and betrays an organization, country, or set of principles.
Apostle: an important early Christian teacher or pioneering missionary.
Apotheosis: the highest point in the development of something; a culmination or climax.
Apothecary: a person who prepared and sold medicines and drugs.