"Freakonomics" is a book written by Steven Levitt and Stephen Dubner (2007) in which the authors discuss the hidden side of some issues affecting us. For example, they present some interrogants such as what is more dangerous: a gun or a pool? or why do drug dealers continue to live with their mothers? Hence, they are not the typical questions asked by economics experts. In this case the given excerpt serves as evidence to support the author's argument since they use statistics taken from different years to ilustrate what the bagel data had to say.
The correct answer is EVIDENCE.