Context: Well , perhaps not lost . They were simply out of place , time , and quite possibly their minds . It was relative , not that she was looking to relate . Different worlds , different times - she did n't know what to think or believe and the mess was too complicated to contemplate in depth when running on fumes .

Question: What may be the reason for " running on fumes " ?
Options:
0. They did n't have their coffee yet .
1. None of the above choices .
2. They did n't get much sleep if any .
3. They did n't have any money for gas .
Answer: 2