Solution :
$$ArCOR$$ can be prepared by the combination of $$ArH + RCOCl$$ and not by $$ArCOCl + RMgX$$ because here the $$ArCOR$$ formed will further react with $$RMgX$$ to form \[{{3}^{\circ }}\] alcohol, \[ArC\left( OH \right){{R}_{2}}\] as the final products.
Releted MCQ Question on Organic Chemistry >> Aldehyde and Ketone
Releted Question 1
The reagent with which both acetaldehyde and acetone react easily is