Which one of the following is not E2 reaction ?
A. `CH_(3)-underset(underset(Cl)|)(C)H-CH_(2)-CH_(3)overset(alc. KOH,Delta)rarr`
B. `CH_(3)-overset(overset(CH_(3))|)(C)H-underset(underset(Br)|)(C)H-CH_(3) overset((CH_(3))_(3)Coverset(o+)(O)K^(o+))rarr`
C.
D. `CH_(3)-underset(underset(CH_(3))|)overset(overset(CH_(3))|)(C)-CH_(2)-Brunderset(Delta)overset(NH_(3)(l))rarr`
