The Doctor looked back when they made it , and saw that the ski lodge was gone . That was n't all , however : the mountain was now disappearing at about the same rate . " Where 's Jack ? " asked Martha , worry in her eyes . " He 'll be here , " said the Doctor .

Question: What may be a plasuible fact about Jack ?
Answer: None of the above choices .Martha cares enough about him to be worried about his absence .Jack decided to leave Martha and the Doctor behind .Martha thinks he is irrelevent enough for her to leave without him .