The audiences for crosswords and Sudoku, understandably, overlap greatly, but there are differences, too. A crossword attracts a more literary person, while Sudoku appeals to a keenly logical mind. Some crossword enthusiasts turn up their noses at Sudoku because they feel it lacks depth. A good crossword requires vocabulary, knowledge, mental flexibility and sometimes even a sense of humor to complete. It touches numerous areas of life and provides an "Aha!" or two along the way._____
The paragraph compares crossword enthusiasts and Sudoku lovers. It emphasizes on the multi-dimensionality of crosswords. So the contrasting sentence, in this context, will be the one which highlights Sudoku as a routine exercise