(1)Assuming the prices HAVE included sales tax
355.55X0.925 =328.88 price before tax
165.65x 0.925=153.13 price discounted
328.88-153.13=175.75 /328.88=0.53 (C) but 175.13/355.55=0.49 not 47%
(2) Assuming the prices have NOT included the sales tax. Still (c) , your calculation. This should be a typical discount calculation.
(3) Assuming sales taxes have NOT been included in the prices BUT is included in the discount calculation , which is unusual.
355.55x1.075=382.22 price after tax
165.65x1.075=178.07 price after tax discounted
382.22-178.07=210.15/382.22=0.55, not 47%
I think you’re right, (c)53%