The question refers to "the following reactions" and asks for the major product $(Y)$, but the reaction scheme/image is missing. Also, the options A–D are blank, so there is no chemical structure to evaluate.

Because of this, the problem cannot be solved from the provided text alone.

What is missing

1. The reaction sequence / reagent list / substrate structure
2. The structures corresponding to options A, B, C, D

Without these, the major product cannot be determined logically.

Comparison with stored answer

The stored correct answer is D, but since the actual reaction and options are not visible, I cannot verify whether D is correct.

Please provide the reaction image or type out:

• the starting compound,
• the reagents/conditions in each step,
• and the structures of options A–D.

Then I can solve it step-by-step properly.