If ZS = RS+jXS, ZL=RL+jXL, then if RL is fixed, the condition for maximum power to be transferred is?

If ZS = RS+jXS, ZL=RL+jXL, then if RL is fixed, the condition for max

1.	If ZS = RS+jXS, ZL=RL+jXL, then if RL is fixed, the condition for maximum power to be transferred is?
A.	XS=XL
B.	XS=-XL
C.	XS+XL=0
D.	None of the mentioned
Answer» C. XS+XL=0