A Paleobotanist's Discovery of a Layer of Sediment from the Quaternary

A paleobotanist's discovery of a layer of sediment from the Quaternary containing fossilized seed fern seeds would be unexpected because

A) no such plants ever existed.
B) seed ferns were extinct by the Quaternary.
C) all material from the Quaternary should be rock, not sediment.
D) seed fern seeds are too soft to fossilize.
E) Quaternary sediments do not have fossils.