The correct answer is (c).
Oral evidence is evidence that is given by a witness in court. It is the most common type of evidence presented in court. Oral evidence can be used to prove any fact, except the contents of documents.
Primary evidence is evidence that is the original document or object. For example, a contract is primary evidence of the terms of the agreement.
Secondary evidence is evidence that is not the original document or object, but is a copy or a summary of the original. For example, a photocopy of a contract is secondary evidence of the terms of the agreement.
Circumstantial evidence is evidence that does not directly prove a fact, but does suggest that the fact is true. For example, if a witness testifies that they saw the defendant running away from the scene of a crime, this is circumstantial evidence that the defendant committed the crime.
In the case of the question, all facts, except the contents of documents, may be proved by oral evidence. This is because oral evidence is the most common type of evidence presented in court, and it can be used to prove any fact, except the contents of documents.