The question asks for the major product $P$, but the actual reaction scheme/structures and the option structures A–D are missing in the prompt.

So, as given, the problem is incomplete and a chemical product cannot be determined reliably.

Step-by-step assessment

1. To identify the major product in an organic reaction, we must know:

   • the starting compound,
   • the reagent(s)/conditions, and
   • the structures of options A, B, C, D.

2. In the current prompt, only this text is present:

   • “Identify major product 'P' formed in the following reaction.”
   • Options listed as A, B, C, D, but with no structures.

3. Since the reaction image/equation is absent, there is no chemically valid way to derive $P$.

4. Therefore, I cannot verify whether option $C$ is actually correct from the provided information.

Conclusion

The question is incomplete. Please provide the reaction scheme/image and the structures of options A–D so I can solve it properly step-by-step.