the answer is A. x-y=5. this is because all that you need to look for to see that it is parallel is a shared slope. y=x+7 has a slope of x and if you move the y over to the other side of your answer you end up with x=y+5, subtract the 5 to isolate the y and you end up with y=x-5. this line also has a slope of x meaning that it is parallel.
