Premise: The Grand Slam tournaments , also called majors , are the four most-important annual tennis events . Martina Navratilova . She won 18 Grand Slam singles titles , 31 major women 's doubles titles ( an all-time record ) , and 10 major mixed doubles titles , marking the open-era record for most Grand Slam titles .
Hypothesis: Martina Navratilova is an athlete.
Label: ENTAILMENT