Full Question:
My supervisor has agreed to replace your unit for free.
Choose the best revision for the first sentence of the opening.
a. We normally honor warranties for only one year from the date of purchase, but your case is different.
b. Please take your car stereo system to our nearest retail location where it will be replaced at no cost.
c. Good news! When you wrote in regarding your car stereo system, we didn’t think we would be able to replace the malfunctioning unit.
Answer:
The correct answer is B)
It contains all the relevant information in the opening sentence as well as lends clarity to how it's going to be done.
Cheers!