A household consists of a married couple, their twin three-year-old sons, and
 their twin eight-year-old daughters. The couple's children had no income and
 lived with their parents all of last year. How many exemptions can the couple
 claim on last year's tax return if they file with the "Married filing jointly" status?
 A. 5
 B. 3
 C. 6
 D. 4