Question: What is the name of the widow of the earl who served as both Foreign Secretary and Prime Minster from 1955 to 1957?
Sentence (from "Clarissa Eden"): Anne Clarissa Eden, Dowager Countess of Avon ("née" Spencer-Churchill; born 28 June 1920) is the widow of Anthony Eden, 1st Earl of Avon (1897–1977), who was British Prime Minister from 1955 to 1957.
Relevant evidence: Yes