Explanation:

- Here’s the thing: Section 21 of the Code of Civil Procedure deals with objections to the jurisdiction of the court, whether it’s about place of suing (territorial), value, or subject-matter.

- Now, the law says you have to raise these objections at “the earliest possible opportunity.” In practice, that means during the trial phase.

- If you wait until appeal or revision to bring up jurisdiction for the first time, you’re too late—unless there has been a “failure of justice.” That’s a high bar.

- So, objections to jurisdiction can be raised in trial, appeal, or revision—but only if you didn’t miss your chance, or if justice has genuinely suffered. The point is, the law allows this in any of these stages, but strongly expects you to do it in the trial first.

- Let’s look at the options:

- Option 1: Trial (not the only stage)

- Option 2: Appeal (possible, but not preferred)

- Option 3: Revision (same logic as appeal)

- Option 4: Either (a) or (b) or (c) (This is correct—it covers all possible stages)