In a certain code language,
(1) 'po ki top ma' means 'Usha is playing cards'.
(2) 'kob ja ki ma' means 'Asha is playing tennis'.
(3) 'ki top so jo' means 'They are playing football'.
(4) 'po sur kob' means 'Cards and tennis'.
Which word in that language means 'Asha'?