Reaction of Z-2 phenyl-2 butene with bromine leads to 63% anti addition and 37% syn addition, while that of Z-2 butene leads to 100% anti addition. This can be explained as:-

A. Formation of an intermediate three membered ring cation- a bromonium ion.
B. Interaction of $$\pi$$-bond of the alkene and diatomic molecule leads to polarization of bromine molecule.
C. Bromonium ion is more stable than the corresponding open carbocation intermediate.
D. Bromonium ion is less stable than the corresponding open carbocation intermediate.