S 3 pts John and Mary have two children, Anna, age 16, and Tammy, age 21, both of whom live with John and Mary and receive >50% of their support from John and Mary. Anna works after school and earned $4,500 in 2018. Tammy works 30 hours per week and is a part-time student at the local community college. She earned $8,400 in 2018. John's mother also lives with them; she receives $2,000 in interest income from some bonds. John and Mary provide over 50% of her support. How many dependents may John and Mary claim on their joint tax return? O O 0 1 3