THE MAN WHO MAILED HIMSELF TO FREEDOM Early in the morning of March 24, 1849, a box arrived at 107 North Fifth Street in Philadelphia. These were the officers of the Pennsylvania Anti-Slavery Society. Several members of this organization had gathered there that Saturday morning, anxiously waiting for the arrival of this package that had come from Richmond, Virginia. After receiving the box, the men locked the door so that there would be no interruptions and one of them did something strange. Leaning over the box, he tapped on it and quietly asked, "Is all right inside?" Even more strangely, a voice replied from inside the box, "All right". Within a few minutes, the men opened the box. Inside was an African-American man in his early thirties by the name of Henry Brown. And he had just succeeded in escaping from slavery by shipping himself to this city in the free state of Pennsylvania. (Krantz C, and Roberts L., 2015, pg. 18.) Krantz C, and Roberts L. (2015). Navigate, coursebook, upper-intermediate. Oxford University Press. According to the text, why did the men lock the door after receiving the box?
a. Because they wanted to hide from their families.
b. Because it was too noisy outside.
c. Because they wanted to avoid interruptions.
d. Because it was too windy.