"Today nobody brought his or her instrument" is correct. It is common for people to use "their" in a sentence like this, but "his or her" is the more proper term.
The sentence that best states the historical significance of "The Selling of Joseph" is: B) This pamphlet calmly disputed the claims that had been made in favor of slavery and provided ordinary citizens and abolitionists with arguments explaining why slavery was wrong.
"The Selling of Joseph" was the first anti-slavery tract published in New England. In it, Sewall condems slavery and refutes many of the era's typical justifications for slavery, warning people of the dire punishment awaiting to those who buy slaves.
This was on my test. According to the reading, answer A is correct. The limit for a well organized speech is 5 main points.