There are two loan markets situated in different regions, each with four banks. In Region A, Bank 1 has 40% of the market share, and Banks 2, 3, and 4 have 20% each. In Region B, Banks 1, 2, and 3 have 30% of the market share each, while Bank 4 has only a 10% market share. Which region is more concentrated, according to the Herfindhal-Hirsch index? a. Region A is more concentrated than Region B. b. Region B is more concentrated than Region A. c. Both regions have the same HHI, 2800. None of the others.