Ko just capped a nine-shot win in Taiwan, her fifth victory of the year and one that returned her to the top spot in the Rolex Rankings. At age 18, she is the youngest player ever to amass 10 career victories and earlier this year she became the youngest woman to ever win a major championship when she captured the Evian Championship.
The Kiwi first became No. 1 in the world at the age of 17, another achievement in her long list of "youngest-ever" accomplishments. After winning twice as an amateur, she won three times last year as an LPGA rookie, including the season-ending CME Group Titleholders. She is expected to represent her native New Zealand next summer when golf returns to the Olympics in Rio de Janeiro.
Ko was one of four athletes on the list, along with snowboarder Chloe Kim, soccer player Martin Odegaard and Olympic swimmer Katie Ledecky. Other entries outside of the world of sports included Malia Obama and reality stars Kendall and Kylie Jenner.