The tone or attitude of the speaker in the case is sad and isolated as the speaker or narrator feels extremely nostalgic and sad as he has to leave the grave of a woman he loved. This tone is expressed mainly through the use of expressions such as "lonesome hill", "her final bed", and "fades from my sight". In the case of "fades from my sight", this is repeated twice to express the desire from the speaker to return to the grave on the hill as even when the hill and grave fades he continues watching it because it seems he does not want to abandon it or forget it as in this place it is the grave of a beloved one. Thus, from the options, it is "fades from my sight" the phrase that contributes to the sad and isolated tone.
The answer would be A.) Fades from my sight. B and C are just stating facts with no tone associated with it. It could possibly be D but A seems the most logical.
