Compound A is an optically active alcohol. Treatment with oxidising agent converts it to a ketone B. In a separate reaction A is treatment with `PBr_(3)`, converting it into C. C on reaction with Mg is added to B to yield
![image](https://learnqa.s3.ap-south-1.amazonaws.com/images/161234058688716549FEu8fZNg1K6kRnMc.png)
. Identify the correct option.
A. A is 2-butanol.
B. A is 1-butanol
C. C is 2-bromobutane
D. C is 1-bromobutane