Frank (48) and Suzanne (51) are married, and they will file a joint return for 2021. During the year, Frank earned $94,000 in wages; Suzanne earned $4,500 from a part-time job. They had no other income. What is the maximum amount the couple may contribute to Suzanne's traditional IRA?
A. $0
B. $4,500
C. $6,000
D. $7,000