Principle :
The answer is: C
Explanation
The most accurate application of the principle in this case is option C: B cannot provide evidence about the oral agreement as it varies from the terms of the written agreement provided in court.
Explanation:
The principle mentioned in Section 92 of the Indian Evidence Act, 1872, is clear in stating that if a contract has been proved by writing, then no evidence can be given of any oral agreement as between the parties to contradict, vary, add to, or subtract from its terms. In this case, A has provided the original written agreement in court, which clearly states that B agreed to pay A Rupees One lakh per year for maintenance services.
B's claim that there was an oral agreement for a lower amount, Rupees Fifty thousand per year, directly contradicts the terms of the written agreement. According to the principle, such oral agreements cannot be used as evidence to vary the terms of the written contract. Therefore, option C is the most accurate application of the principle in this case.