In 2017, Tom and Darla, a married couple, were employed all year. They each worked for only one employer the entire year. Tom paid Social Security taxes (SST) in the amount of $4,373, and Darla paid $8,188.80. What is the amount of their excess SST which they can claim as a credit? a) $4,675.40 $ 302.40 C 0.00 d $841.80