Which linear Diophantine equation has NO integer solutions?
12x+8y=412x + 8y = 412x+8y=4
9x+15y=39x + 15y = 39x+15y=3
10x+15y=510x + 15y = 510x+15y=5
6x+9y=76x + 9y = 76x+9y=7