Answer: Option (A). Britain rise as the dominant world power
Explanation: Britain rise as the dominant world power is an historical event most likely shaped the cultural values of British society in the 1800s. British culture is also affected by the nation's history, its predominantly Christian religious life, its interaction with the cultures of Europe, the tradition of United Kingdom, and the impact of the British Empire. Although British culture is a distinct entity, the individual cultures of England, Scotland, Wales and Northern Ireland are diverse and have varying degrees of overlap and distinctiveness.
B gives the best summary of the paragraph
The most appropriate language is formal language
Assure could mean making sure something happens, to comfort or remove doubts from a person, or make someone sure of something.
If it's one word answers it could be persuading, guaranteeing, promising, convincing, reassure, satisfy, or tell.
I hope this helps without answer choices it's kind of hard to know what kind of answer you need. Have a great day!