Which of the following pair of linear equations is inconsistent?
A. x - 2y = 6; 2x + 3y = 4
B. 9x - 8y = 17; 18x -16y = 34
C. 2x + 3y = 7; 4x + 6y = 5
D. 5x - 3y =11; 7x + 2y =13