The question as provided is incomplete: the reaction sequence image/structure and the actual options A–D are missing.

Because of that, the major products $A$ and $B$ cannot be determined from the text alone.

What is missing

To solve this, I would need:

1. The starting compound(s)
2. The reagents/conditions in the reaction sequence
3. The option structures corresponding to choices A, B, C, D

Why I cannot verify the stored answer

Although the stored correct answer is given as C, there is no chemical information available here to independently derive whether option C is correct.

So, from the available data, the problem is unsolvable.

Conclusion

Please upload or type the reaction scheme and the option structures. Once those are provided, I can solve it step-by-step and verify whether option C is correct.