A.One of the students asked him about it in the previous class.
B.He read about it the previous day.
C.He had just read Dr. Frederick Cock's travel log
D.The students were required to read about it for that day's class
A.Pierre had announced his success prematurely.
B.The investigation of Pierre's expedition wasn't thorough.
C.Pierre wasn't an experienced explorer.
D.He had reached the pole before Pierre did.
A.They talked to one of Pierre's companions.
B.They interviewed Pierre.
C.They conducted a computer analysis of photographs.
D.They examined Pierre's navigation tools,