Correct Option: D

Martina Hingis is a Swiss former professional tennis player who spent a total of 209 weeks as World No. 1. She won five Grand Slam singles titles (three Australian Opens, one Wimbledon, and one US Open). She also won nine Grand Slam women’s doubles titles, winning a calendar year doubles Grand Slam in 1998, and one Grand Slam mixed doubles title. Hingis set a series of “youngest-ever” records before ligament injuries in both ankles forced her to withdraw temporarily from professional tennis in 2002 at the age of 22. In 1996, Hingis became the youngest Grand Slam champion of all time, when she teamed with Helena Suková at Wimbledon to win the women’s doubles title at age 15 years and 9 months.