What sequence of steps represents the best synthesis of 2-heptanol? a) CH3CH2CH2MgBr (2 moles) + formaldehyde in diethyl ether followed by H3O+ b) CH3CH2CH2CH2MgBr + butanal in diethyl ether followed by H3O+ c) CH3CH2CH2CH2MgBr + acetone in diethyl ether followed by H3O+ d) CH3CH2CH2CH2CH2MgBr + ethanal in diethyl ether followed by H3O+