Under common reaction conditions, a carboncation rearranges to another carbocation of equal or greater stability. For example secondary carbocation will rearrange to a tertiary carbocation. It will not rearrange to a less stable primary carbocation. This generalization is not absolute, and because there is not is a high energy barrier to the rearrangement of carbocations, rearrangement to a less stable cation can occur if it offers the chance to forme a more stable product.
In which of the following cations rearrangement takes place?
A.
B.
C.
D.