When man has the right to do karma, he has the right to the fruit of karma too. It cannot be said that he has not; there is no way to say it. But the meaning is this: "The fruit of karma must be given up willingly." That is why the Gītā has shown a path: Do the work; give up the fruit. Desire for the fruit is rajoguṇa. To give up the work itself, thinking there is no fruit, is tamoguṇa. So the Gītā shows the divine path: doing the work and giving up the fruit becomes sattvaguṇa.