PLEASE HELP TRYING TO MAKE HONOR ROLL < PLEASE HELP ME OUT

Which equation has exactly one solution?
A. 1/2x-2=2x-1/2
B. 1/2x-2=1/2x+2
C. 1/2x-2=1/2x+ -1/2
D. 1/2x-1/2=1/2x+2