The Principal Reason We Consider Tunicates (Sea Squirts) Similar to the Ancestor

The principal reason we consider tunicates (sea squirts) similar to the ancestor of all chordates is that

A) the body plan of adult tunicates parallels that of chordates.
B) tunicate larvae possess the synapomorphies of adult chordates and thus reveal close evolutionary relationships with them.
C) tunicates have a lophophore-style mouth.
D) tunicate larvae are primitive in all of their features.
E) tunicate adults are very similar to the ancestors of cephalochordates and vertebrates.