cannot be prepared by :
(1) HCHO + PhCH(CH3)CH2Mgx
(2) PhCOCH2CH3 + CH3MgX
(3) CH3CH2COCH3 + PhMgX
(4) PhCOCH3 + CH3CH2MgX
The correct option (1) HCHO + PhCH(CH3)CH2Mgx
Explanation: