We call literal language when we say exactly what we mean, when the words selected convey a meaning by themselves, there is no need for context, for further explanation or revision of intonation, inflection or body language or gestures or other non-verbal component.
In literal language you say exactly what the words you selected were intended to mean from the moments they were created.
On the other hand, Non-literal language contains a lot of hidden connotations, it has double sense, between the lines meaning and we usually need the right context to understand it.
To answer this question, when language is non literal:
C. You must use inference skills to determine the meaning