Lydia and John Wickham Filed Jointly in Year 1

Multiple Choice

Lydia and John Wickham filed jointly in year 1. They divorced in year 2. Late in year 2, the IRS discovered that the Wickham's underpaid their year 1 taxes by $2,000. Both Lydia and John worked in year 1 and received equal income but John had $2,000 less tax withheld than did Lydia. Who is legally liable for the tax underpayment?

A) Lydia.
B) John.
C) Both Lydia and John.
D) Neither Lydia nor John.