# Why does (3E)-3,4-dimethylhex-3-ene yield a meso dihalide when reacted with Br2/CCl4 at room temperature?

The answer is B. But why? What makes it so different than the others? I know that it attacks from the back (anti addition). But can't it do that for all and result in a meso compound?

Using this knowledge, and given that $\ce{Br2}$ undergoes anti addition to alkenes, there are only really two answers that could possibly be meso compounds, B and D. Let us consider the products: