The question refers to “the above reactions”, but the actual reaction scheme/image is missing. Also, the options are shown only as placeholders:

• A:
• B:
• C:
• D:

So the chemical transformations needed to identify compounds ‘A’ and ‘B’ are not available.

What can be concluded?

Without the reaction sequence, structures, reagents, or actual answer options, the problem cannot be solved from chemistry reasoning alone.

Comparison with stored correct answer

The stored correct answer is B, but since the reaction scheme is absent, I cannot independently verify whether B is actually correct.

What is needed to solve it?

Please provide one of the following:

1. The full reaction sequence/image, or
2. The text of the reactions, and
3. The actual four options.

Then I can solve it step-by-step and verify the correct choice properly.