Final answer:
The Book of Common Prayer was the Protestant liturgy book written during Edward VI's reign and mandated for use in the Church of England. It represented a compromise between Catholic traditions and Protestant reforms, significantly shaping Anglican worship. Option A is the correct answer.
Step-by-step explanation:
During the reign of Edward VI, the Protestant liturgy book that was written and required to be used by all congregations in the Church of England is A) the Book of Common Prayer. The Book of Common Prayer played a pivotal role in establishing Anglican religious practices and was a significant tool for the Protestant Reformation in England. This book was a compromise between the Catholic beliefs of the time and the emerging Protestant views, allowing for changes such as priests marrying and the Eucharist becoming a commemorative act rather than one involving transubstantiation. It marked a decisive shift away from Catholic rituals, reflected in the Elizabethan Religious Settlement and the Act of Uniformity of 1559, which solidified the Church of England's practices.