What is the athletic conference called that includes both Ohio State University and Purdue University?

The Big Ten Conference is the correct answer because it is the athletic conference that includes both Ohio State University and Purdue University, along with several other prominent universities in the Midwest. It was founded in 1896 and is known for its strong academic institutions as well as its competitive athletic programs, particularly in basketball and football.

The conference includes schools that have rich traditions in collegiate athletics, and both Ohio State and Purdue have a long history within the Big Ten, competing against each other and other member schools in various sports. The Big Ten encompasses schools that are often recognized for their athletic and academic excellence, making it an influential conference in the NCAA landscape.

The other answer choices represent different conferences. The Pacific-10 is a former conference primarily for schools on the West Coast, while the Big Five and Southwest Conference do not pertain to the schools listed in the question. The Big Five typically refers to the major basketball conferences from which teams belong to the NCAA Football Bowl Subdivision, while the Southwest Conference no longer exists and was primarily based in the southern United States.