Read the following context and choose the best option to answer the question.
Context: We were still new at this and had n't learnt to be selective with excursions . Fifteen kilometres behind the Nullabor Roadhouse are three caves formed underground by collapsed land . We got instructions on how to get there from the roadhouse staff , left the camper behind and drove off into the scrub . Soon , all we could see was the horizon , so flat was the landscape in all directions .
Question: Where are they heading to ?
Options: 
A. They are going underground .
B. They are going on a trip .
C. They are going to the caves .
D. None of the above choices .


C