Which one of the following react with gringnard reagent followed by hydrolysis will yield primary alcohol?

Which one of the following react with gringnard reagent followed by hy

1.	Which one of the following react with gringnard reagent followed by hydrolysis will yield primary alcohol?
Answer» `CH_3CHO` `HCHO` `CH_3COCH_3` `CO_2` SOLUTION :`HCHO`