I prefer to say a coding strand and a template strand. Temmplate strand is complementary to the coding strand and it is the coding strand where mRNA forms. So, if the coding strand says ACG the template strand will say TGC and mRNA will be UCG. In the case of your question, I think they are asking for the base sequence on the template strand. Re-read the question. I think the question is, in fact, asking for the template strand code.