Grignard reagents (RMgX) are sensitive to moisture and will react with water to form alkanes, precluding the intended reaction. Therefore, anhydrous conditions are essential for their preparation and storage.
Observe the following reaction and same reaction is carried out with the following compound: 
X and Y can be differentiated by:
A student is given one compound among the following compounds that gives positive test with Tollen's reagent. The compound is: 