Who are the chosen ones whom Allah made inheritors of the Book in His saying, "Then We made to inherit the Book those We chose from Our servants"?

Allah chose the nation of Muhammad, may Allah's prayers and peace be upon him, and bequeathed to them the Qur'an. They are of three types: one who wrongs himself, whom Allah forgives; one who is moderate, who will be judged with an easy reckoning; and one who is foremost in good deeds, who will enter Paradise without reckoning.