John earned $500,000 in his business during the current year, and his wife received investment income of $15,000. John provides more than half of the support of his widowed sister, who lives with John and earned $45,000 in salary. John also provides full support for his two children, an 18-year-old daughter and a 20-year-old son, who is a full-time college student. The family employs a live-in housekeeper and a live-in butler to assist them with their residence. What is the maximum number of dependents that John and his wife are eligible to claim?

Three dependents.

Five dependents.

Two dependents.

Seven dependents.