D, explanation: although B seems correct, D is more correct since it directly affects the graph. Algebraicly, plug in 3 for y to get 3=(1/2)^x+3 subtracting 3 gives us a zero, and an exponent cannot equal zero. B is -3=(1/2)^x and this particular exponent cannot equal a negative since the base is positive. If possible choose both, but D would be better if you could only choose one
