Depending on your TRE, there's the possibility of 2 wrong answers to this scenario. I agree with the general thrust of the answers so far, especially by my god ol' mate Checkboard.
I think the point is that, whatever decision you make - no matter how impossibly unrealistic the scenario, you better have thought it though quickly so that you can justify why you did what you ultimately did and, equally importantly, why you didn't take the alternative option. This is what a TRE is likely to be looking for when assessing a candidate for command.
It has been said many times before, in many different ways, applying to many different types of transport medium - "When in command... Command!"