Which of these do not from Grignard reagent ?

Which of these does not form Grignard reagent?

Grignard reagent is usually prepared by R-X+Mg overset(Et_(2)O)rarrRMgX " " "Grignard reagent" Ar-X+Mg overset(Et_(2)O)rarrArMgX " " "Grignard reagent" Grignard reagent acts s a strong base. Grignard reagent carry out nucleoplilic attack in absence of acidic hydrogen. Grignard reagent form complex with its ether solvent. Complex formation with molecule of ether is an important factor in the formation and stability of Grignard reagent. Which of the following Grignard reagents is not possible ?

Which of the following Grignard reagent can be prepared ?