I looked at 5 job openings (randomly selected) that came up when I searched Indeed.com for “Management Consulting firm entry level.” Three required a bachelor’s degree without specifying a field (with one of them saying “Graduate degree in Business, Industrial / Organizational psychology, Human Resources, Organizational behavior, or related psychology field preferred”). One said bachelor’s in a STEM field and one said, “Bachelors degree or equivalent in business, management information systems, human resources management, benefits administration or related field; Masters degree a plus.” What does this small data set suggest? People are accepted with a wide array of majors, but business, psychology and human resources seem particularly desired. In some (STEM) industries a STEM degree may be desired.
http://www.census.gov/dataviz/visualizations/stem/stem-html/ (choose the Non-STEM Majors tab and hold your mouse over the Business and financial occupational group) shows most people in that field having majored in business.