The question asks for the major product $X$, but the actual reaction scheme/structures are missing, and all four options $A, B, C, D$ are blank in the prompt.

So, the reaction cannot be analyzed from the given information.

Step 1: What is needed to solve this?

To identify the major product in organic chemistry, we must know:

1. The starting compound
2. The reagents/conditions
3. The structures of options $A, B, C, D$

None of these are visible here.

Step 2: Can the stored answer be verified?

The stored correct answer is given as A, but since the reaction and options are absent, there is no chemical basis to independently derive or verify that answer.

Step 3: Conclusion

Because the reaction figure/options are missing, the problem is incomplete, and the major product cannot be determined from the provided text alone.

Please upload or paste the reaction scheme and option structures so I can solve it step-by-step properly.