In SN2 reactions, the correct order of reactivity for the following compounds CH3Cl, CH3CH2Cl, (CH3)2CHCl and (CH3)3CCl is
-
CH3Cl > (CH3)2CHCl >CH3CH2Cl > (CH3)3CCl
-
CH3Cl > CH3CH2Cl > (CH3)2CHCl >(CH3)3CCl
-
CH3CH2Cl > CH3Cl >(CH3)2CHCl >(CH3)3CCl
-
(CH3)2CHCl > CH3CH2Cl > CH3Cl >(CH3)3CCl
B.
CH3Cl > CH3CH2Cl > (CH3)2CHCl >(CH3)3CCl

As steric hindrance (crowding) increases, the rate of SN2 reaction decreases.
Primary halides > Secondary halides >Tertiary halides