Step 1: Understanding summary suits.
A summary suit is a special legal procedure where the defendant has limited rights to defend, designed for quick resolution of cases involving liquidated claims such as bills of exchange or promissory notes.
Step 2: Relevant provision.
Order XXXVII of the Code of Civil Procedure (CPC) deals with the procedure for summary suits. It simplifies litigation by allowing the plaintiff to obtain a decree quickly when the defendant fails to present a substantial defence.
Step 3: Conclusion.
Thus, the correct answer is Order XXXVII of CPC.