Read the following context and choose the best option to answer the question.
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: 
A. They did n't have their coffee yet .
B. None of the above choices .
C. They did n't get much sleep if any .
D. They did n't have any money for gas .


C