Karl, Lim, Mary and Navin are each competing in a different sporting event at the Olympic Games - basketball, swimming, taekwondo and women\textquotesingle s rhythmic gymnastics. Karl and Navin do not know how to swim. Mary is the only female. Karl\textquotesingle s event does not require a ball. Which event is Navin competing in? 
选项为:A:Basketball　  B:Swimming　  C:Taekwondo　  D:Rhythmic gymnastics　  请回答其中一个选项.