The correct answer is that there were $51,700 work of gift cards redeemed during the year.
In order to determine the correct answer you need to start with the total balance of the unearned revenue account, which is $6,800. To the starting balance you need to add the amount of gift cards purchased throughout the year, which is $55,000. This total is $61,800. The last step is to subtract the ending balance of the unearned revenue from the total ($61,800 - 10,100), which equals $51,700. $51,700 is the amount of gift cards redeemed during the year.