The correct answer is parenthesis. A parenthesis normally appears in sentences when extra information unrelated to the main idea of the sentence is inserted. The trick in knowing if a phrase can be included in a parenthesis is when you take it out and the idea of the sentence is intact.
Chinua Achebe was a Nigerian novelist. He had a title of chieftain of Igbo tribe and wrote novels about its customs. That was portrayed as sophisticated, passed down through generations.
Westerners may mistaken them as ‘primitive and savage’. But Achebe showed Igbo people's rich cultural background through his narrations. Igbo proverbs, ‘the art of conversation", were frequently quoted in his novels.
The non-violent nature of Igbo was demonstrated by events like the peaceful agreement with the Mbaino tribe during a murder in Igbo by a Mbaino man.
An antagonist is a character, group of characters, institution or concept that stands in or represents opposition against which the protagonist(s) must contend. In other words, an antagonist is a person or a group of people who opposes a protagonist.
B) Authoritative but humorous