final fantasy x-2 ?

when i start the game there is two option : final fantasy x-2 and final fantasy x-2 last mission , what the different and which one i play first ?

Neither

Play X-2 first, Last Mission takes place three months after X-2. X-2 in the HD Remaster is the international version and it was an exclusive in Japan so the only difference the feel, speed, look and dialogue with extra content.