The answer is: B
Explanation
The correct option is B: The court of the lowest grade.
Section 15 of the Code of Civil Procedure (CPC) states that every suit shall be instituted in the court of the lowest grade competent to try it. This means that the court must have the power to hear the case with regard to pecuniary jurisdiction, which is the monetary value of the subject matter of the suit. The purpose of this rule is to avoid unnecessary burden on the higher courts and to ensure speedy disposal of cases. The court of the lowest grade may be a district court, a subordinate court, or a small cause court, depending on the nature and value of the suit. If there are more than one court of the lowest grade having jurisdiction over the suit, then the plaintiff may choose any one of them.